diff --git a/Source/Core/DolphinQt/RenderWidget.cpp b/Source/Core/DolphinQt/RenderWidget.cpp
@@ -32,9 +32,16 @@
 #include "DolphinQt/Resources.h"
 #include "DolphinQt/Settings.h"
 
+#include "InputCommon/ControllerInterface/ControllerInterface.h"
+
 #include "VideoCommon/RenderBase.h"
 #include "VideoCommon/VideoConfig.h"
 
+#ifdef _WIN32
+#include <WinUser.h>
+#include <windef.h>
+#endif
+
 RenderWidget::RenderWidget(QWidget* parent) : QWidget(parent)
 {
   setWindowTitle(QStringLiteral("Dolphin"));
@@ -79,7 +86,10 @@ RenderWidget::RenderWidget(QWidget* parent) : QWidget(parent)
 
   connect(&Settings::Instance(), &Settings::HideCursorChanged, this,
           &RenderWidget::OnHideCursorChanged);
+  connect(&Settings::Instance(), &Settings::LockCursorChanged, this,
+          &RenderWidget::OnLockCursorChanged);
   OnHideCursorChanged();
+  OnLockCursorChanged();
   connect(&Settings::Instance(), &Settings::KeepWindowOnTopChanged, this,
           &RenderWidget::OnKeepOnTopChanged);
   OnKeepOnTopChanged(Settings::Instance().IsKeepWindowOnTopEnabled());
@@ -128,7 +138,33 @@ void RenderWidget::dropEvent(QDropEvent* event)
 
 void RenderWidget::OnHideCursorChanged()
 {
-  setCursor(Settings::Instance().GetHideCursor() ? Qt::BlankCursor : Qt::ArrowCursor);
+  UpdateCursor();
+}
+void RenderWidget::OnLockCursorChanged()
+{
+  SetCursorLocked(false);
+  UpdateCursor();
+}
+
+// Calling this at any time will set the cursor (image) to the correct state
+void RenderWidget::UpdateCursor()
+{
+  if (!Settings::Instance().GetLockCursor())
+  {
+    // Only hide if the cursor is automatically locking (it will hide on lock).
+    // "Unhide" the cursor if we lost focus, otherwise it will disappear when hovering
+    // on top of the game window in the background
+    const bool keep_on_top = (windowFlags() & Qt::WindowStaysOnTopHint) != 0;
+    const bool should_hide =
+        Settings::Instance().GetHideCursor() &&
+        (keep_on_top || SConfig::GetInstance().m_BackgroundInput || isActiveWindow());
+    setCursor(should_hide ? Qt::BlankCursor : Qt::ArrowCursor);
+  }
+  else
+  {
+    setCursor((m_cursor_locked && Settings::Instance().GetHideCursor()) ? Qt::BlankCursor :
+                                                                          Qt::ArrowCursor);
+  }
 }
 
 void RenderWidget::OnKeepOnTopChanged(bool top)
@@ -138,14 +174,22 @@ void RenderWidget::OnKeepOnTopChanged(bool top)
   setWindowFlags(top ? windowFlags() | Qt::WindowStaysOnTopHint :
                        windowFlags() & ~Qt::WindowStaysOnTopHint);
 
+  m_dont_lock_cursor_on_show = true;
   if (was_visible)
     show();
+  m_dont_lock_cursor_on_show = false;
+
+  UpdateCursor();
 }
 
 void RenderWidget::HandleCursorTimer()
 {
-  if (isActiveWindow())
+  if (!isActiveWindow())
+    return;
+  if (!Settings::Instance().GetLockCursor() || m_cursor_locked)
+  {
     setCursor(Qt::BlankCursor);
+  }
 }
 
 void RenderWidget::showFullScreen()
@@ -159,6 +203,138 @@ void RenderWidget::showFullScreen()
   emit SizeChanged(width() * dpr, height() * dpr);
 }
 
+// Lock the cursor within the window/widget internal borders, including the aspect ratio if wanted
+void RenderWidget::SetCursorLocked(bool locked, bool follow_aspect_ratio)
+{
+  // It seems like QT doesn't scale the window frame correctly with some DPIs
+  // so it might happen that the locked cursor can be on the frame of the window,
+  // being able to resize it, but that is a minor problem.
+  // As a hack, if necessary, we could always scale down the size by 2 pixel, to a min of 1 given
+  // that the size can be 0 already. We probably shouldn't scale axes already scaled by aspect ratio
+  QRect render_rect = geometry();
+  if (parentWidget())
+  {
+    render_rect.moveTopLeft(parentWidget()->mapToGlobal(render_rect.topLeft()));
+  }
+  auto scale = devicePixelRatioF();  // Seems to always be rounded on Win. Should we round results?
+  QPoint screen_offset = QPoint(0, 0);
+  if (window()->windowHandle() && window()->windowHandle()->screen())
+  {
+    screen_offset = window()->windowHandle()->screen()->geometry().topLeft();
+  }
+  render_rect.moveTopLeft(((render_rect.topLeft() - screen_offset) * scale) + screen_offset);
+  render_rect.setSize(render_rect.size() * scale);
+
+  if (follow_aspect_ratio)
+  {
+    // TODO: SetCursorLocked() should be re-called every time this value is changed?
+    // This might cause imprecisions of one pixel (but it won't cause the cursor to go over borders)
+    Common::Vec2 aspect_ratio = g_controller_interface.GetWindowInputScale();
+    if (aspect_ratio.x > 1.f)
+    {
+      const float new_half_width = float(render_rect.width()) / (aspect_ratio.x * 2.f);
+      // Only ceil if it was >= 0.25
+      const float ceiled_new_half_width = std::ceil(std::round(new_half_width * 2.f) / 2.f);
+      const int x_center = render_rect.center().x();
+      // Make a guess on which one to floor and ceil.
+      // For more precision, we should have kept the rounding point scale from above as well.
+      render_rect.setLeft(x_center - std::floor(new_half_width));
+      render_rect.setRight(x_center + ceiled_new_half_width);
+    }
+    if (aspect_ratio.y > 1.f)
+    {
+      const float new_half_height = render_rect.height() / (aspect_ratio.y * 2.f);
+      const float ceiled_new_half_height = std::ceil(std::round(new_half_height * 2.f) / 2.f);
+      const int y_center = render_rect.center().y();
+      render_rect.setTop(y_center - std::floor(new_half_height));
+      render_rect.setBottom(y_center + ceiled_new_half_height);
+    }
+  }
+
+  if (locked)
+  {
+#ifdef _WIN32
+    RECT rect;
+    rect.left = render_rect.left();
+    rect.right = render_rect.right();
+    rect.top = render_rect.top();
+    rect.bottom = render_rect.bottom();
+
+    if (ClipCursor(&rect))
+#else
+    // TODO: implement on other platforms. Probably XGrabPointer on Linux.
+    // The setting is hidden in the UI if not implemented
+    if (false)
+#endif
+    {
+      m_cursor_locked = true;
+
+      if (Settings::Instance().GetHideCursor())
+      {
+        setCursor(Qt::BlankCursor);
+      }
+
+      Host::GetInstance()->SetRenderFullFocus(true);
+    }
+  }
+  else
+  {
+#ifdef _WIN32
+    ClipCursor(nullptr);
+#endif
+
+    if (m_cursor_locked)
+    {
+      m_cursor_locked = false;
+
+      if (!Settings::Instance().GetLockCursor())
+      {
+        return;
+      }
+
+      // Center the mouse in the window if it's still active
+      // Leave it where it was otherwise, e.g. a prompt has opened or we alt tabbed.
+      if (isActiveWindow())
+      {
+        cursor().setPos(render_rect.left() + render_rect.width() / 2,
+                        render_rect.top() + render_rect.height() / 2);
+      }
+
+      // Show the cursor or the user won't know the mouse is now unlocked
+      setCursor(Qt::ArrowCursor);
+
+      Host::GetInstance()->SetRenderFullFocus(false);
+    }
+  }
+}
+
+void RenderWidget::SetCursorLockedOnNextActivation(bool locked)
+{
+  if (Settings::Instance().GetLockCursor())
+  {
+    m_lock_cursor_on_next_activation = locked;
+    return;
+  }
+  m_lock_cursor_on_next_activation = false;
+}
+
+void RenderWidget::SetWaitingForMessageBox(bool waiting_for_message_box)
+{
+  if (m_waiting_for_message_box == waiting_for_message_box)
+  {
+    return;
+  }
+  m_waiting_for_message_box = waiting_for_message_box;
+  if (!m_waiting_for_message_box && m_lock_cursor_on_next_activation && isActiveWindow())
+  {
+    if (Settings::Instance().GetLockCursor())
+    {
+      SetCursorLocked(true);
+    }
+    m_lock_cursor_on_next_activation = false;
+  }
+}
+
 bool RenderWidget::event(QEvent* event)
 {
   PassEventToImGui(event);
@@ -178,23 +354,67 @@ bool RenderWidget::event(QEvent* event)
 
     break;
   }
+  // Needed in case a new window open and it moves the mouse
+  case QEvent::WindowBlocked:
+    SetCursorLocked(false);
+    break;
   case QEvent::MouseButtonPress:
-    if (!Settings::Instance().GetHideCursor() && isActiveWindow())
+    if (isActiveWindow())
     {
-      setCursor(Qt::ArrowCursor);
-      m_mouse_timer->start(MOUSE_HIDE_DELAY);
+      // Lock the cursor with any mouse button click (behave the same as window focus change).
+      // This event is occasionally missed because isActiveWindow is laggy
+      if (Settings::Instance().GetLockCursor() && event->type() == QEvent::MouseButtonPress)
+      {
+        SetCursorLocked(true);
+      }
+      // Unhide on movement
+      if (!Settings::Instance().GetHideCursor())
+      {
+        setCursor(Qt::ArrowCursor);
+        m_mouse_timer->start(MOUSE_HIDE_DELAY);
+      }
     }
     break;
   case QEvent::WinIdChange:
     emit HandleChanged(reinterpret_cast<void*>(winId()));
     break;
+  case QEvent::Show:
+    // Don't do if "stay on top" changed (or was true)
+    if (Settings::Instance().GetLockCursor() && Settings::Instance().GetHideCursor() &&
+        !m_dont_lock_cursor_on_show)
+    {
+      // Auto lock when this window is shown (it was hidden)
+      if (isActiveWindow())
+        SetCursorLocked(true);
+      else
+        SetCursorLockedOnNextActivation();
+    }
+    break;
+  // Note that this event in Windows is not always aligned to the window that is highlighted,
+  // it's the window that has keyboard and mouse focus
   case QEvent::WindowActivate:
     if (SConfig::GetInstance().m_PauseOnFocusLost && Core::GetState() == Core::State::Paused)
       Core::SetState(Core::State::Running);
 
+    UpdateCursor();
+
+    // Avoid "race conditions" with message boxes
+    if (m_lock_cursor_on_next_activation && !m_waiting_for_message_box)
+    {
+      if (Settings::Instance().GetLockCursor())
+      {
+        SetCursorLocked(true);
+      }
+      m_lock_cursor_on_next_activation = false;
+    }
+
     emit FocusChanged(true);
     break;
   case QEvent::WindowDeactivate:
+    SetCursorLocked(false);
+
+    UpdateCursor();
+
     if (SConfig::GetInstance().m_PauseOnFocusLost && Core::GetState() == Core::State::Running)
     {
       // If we are declared as the CPU thread, it means that the real CPU thread is waiting
@@ -206,8 +426,13 @@ bool RenderWidget::event(QEvent* event)
 
     emit FocusChanged(false);
     break;
+  case QEvent::Move:
+    SetCursorLocked(m_cursor_locked);
+    break;
   case QEvent::Resize:
   {
+    SetCursorLocked(m_cursor_locked);
+
     const QResizeEvent* se = static_cast<QResizeEvent*>(event);
     QSize new_size = se->size();
 
@@ -218,14 +443,18 @@ bool RenderWidget::event(QEvent* event)
     emit SizeChanged(new_size.width() * dpr, new_size.height() * dpr);
     break;
   }
+  // Happens when we add/remove the widget from the main window instead of the dedicated one
+  case QEvent::ParentChange:
+    SetCursorLocked(false);
+    break;
   case QEvent::WindowStateChange:
+    // Lock the mouse again when fullscreen changes (we might have missed some events)
+    SetCursorLocked(m_cursor_locked || (isFullScreen() && Settings::Instance().GetLockCursor()));
     emit StateChanged(isFullScreen());
     break;
   case QEvent::Close:
     emit Closed();
     break;
-  default:
-    break;
   }
   return QWidget::event(event);
 }

diff --git a/Source/Core/DolphinQt/RenderWidget.h b/Source/Core/DolphinQt/RenderWidget.h
@@ -20,6 +20,10 @@ class RenderWidget final : public QWidget
   bool event(QEvent* event) override;
   void showFullScreen();
   QPaintEngine* paintEngine() const override;
+  bool IsCursorLocked() const { return m_cursor_locked; }
+  void SetCursorLockedOnNextActivation(bool locked = true);
+  void SetWaitingForMessageBox(bool waiting_for_message_box);
+  void SetCursorLocked(bool locked, bool follow_aspect_ratio = true);
 
 signals:
   void EscapePressed();
@@ -32,7 +36,9 @@ class RenderWidget final : public QWidget
 private:
   void HandleCursorTimer();
   void OnHideCursorChanged();
+  void OnLockCursorChanged();
   void OnKeepOnTopChanged(bool top);
+  void UpdateCursor();
   void PassEventToImGui(const QEvent* event);
   void SetImGuiKeyMap();
   void dragEnterEvent(QDragEnterEvent* event) override;
@@ -41,4 +47,8 @@ class RenderWidget final : public QWidget
   static constexpr int MOUSE_HIDE_DELAY = 3000;
   QTimer* m_mouse_timer;
   QPoint m_last_mouse{};
+  bool m_cursor_locked = false;
+  bool m_lock_cursor_on_next_activation = false;
+  bool m_dont_lock_cursor_on_show = false;
+  bool m_waiting_for_message_box = false;
 };
diff --git a/Source/Core/DolphinQt/Settings.cpp b/Source/Core/DolphinQt/Settings.cpp
@@ -280,6 +280,17 @@ bool Settings::GetHideCursor() const
   return SConfig::GetInstance().bHideCursor;
 }
 
+void Settings::SetLockCursor(bool lock_cursor)
+{
+  SConfig::GetInstance().bLockCursor = lock_cursor;
+  emit LockCursorChanged();
+}
+
+bool Settings::GetLockCursor() const
+{
+  return SConfig::GetInstance().bLockCursor;
+}
+
 void Settings::SetKeepWindowOnTop(bool top)
 {
   if (IsKeepWindowOnTopEnabled() == top)

diff --git a/Source/Core/DolphinQt/Settings.h b/Source/Core/DolphinQt/Settings.h
@@ -100,6 +100,8 @@ class Settings final : public QObject
   // Graphics
   void SetHideCursor(bool hide_cursor);
   bool GetHideCursor() const;
+  void SetLockCursor(bool lock_cursor);
+  bool GetLockCursor() const;
   void SetKeepWindowOnTop(bool top);
   bool IsKeepWindowOnTopEnabled() const;
 
@@ -168,6 +170,7 @@ class Settings final : public QObject
   void MetadataRefreshCompleted();
   void AutoRefreshToggled(bool enabled);
   void HideCursorChanged();
+  void LockCursorChanged();
   void KeepWindowOnTopChanged(bool top);
   void VolumeChanged(int volume);
   void NANDRefresh();

diff --git a/Source/Core/DolphinQt/Settings/InterfacePane.cpp b/Source/Core/DolphinQt/Settings/InterfacePane.cpp
@@ -171,6 +171,14 @@ void InterfacePane::CreateInGame()
   m_checkbox_show_active_title = new QCheckBox(tr("Show Active Title in Window Title"));
   m_checkbox_pause_on_focus_lost = new QCheckBox(tr("Pause on Focus Loss"));
   m_checkbox_hide_mouse = new QCheckBox(tr("Always Hide Mouse Cursor"));
+  m_checkbox_lock_mouse = new QCheckBox(tr("Lock Mouse Cursor"));
+
+  m_checkbox_hide_mouse->setToolTip(
+      tr("Will immediately hide the Mouse Cursor when it hovers on top of the Render Widget, "
+         "otherwise "
+         "there is a delay.\nIf \"Lock Mouse Cursor\" is enabled, it will hide on Mouse locked"));
+  m_checkbox_lock_mouse->setToolTip(tr("Will lock the Mouse Cursor to the Render Widget as long as "
+                                       "it has focus. You can set a hotkey to unlock it."));
 
   groupbox_layout->addWidget(m_checkbox_top_window);
   groupbox_layout->addWidget(m_checkbox_confirm_on_stop);
@@ -179,6 +187,9 @@ void InterfacePane::CreateInGame()
   groupbox_layout->addWidget(m_checkbox_show_active_title);
   groupbox_layout->addWidget(m_checkbox_pause_on_focus_lost);
   groupbox_layout->addWidget(m_checkbox_hide_mouse);
+#ifdef _WIN32
+  groupbox_layout->addWidget(m_checkbox_lock_mouse);
+#endif
 }
 
 void InterfacePane::ConnectLayout()
@@ -203,6 +214,8 @@ void InterfacePane::ConnectLayout()
   connect(m_checkbox_pause_on_focus_lost, &QCheckBox::toggled, this, &InterfacePane::OnSaveConfig);
   connect(m_checkbox_hide_mouse, &QCheckBox::toggled, &Settings::Instance(),
           &Settings::SetHideCursor);
+  connect(m_checkbox_lock_mouse, &QCheckBox::toggled, &Settings::Instance(),
+          &Settings::SetLockCursor);
   connect(m_checkbox_use_userstyle, &QCheckBox::toggled, this, &InterfacePane::OnSaveConfig);
 }
 
@@ -239,6 +252,7 @@ void InterfacePane::LoadConfig()
   m_checkbox_use_covers->setChecked(Config::Get(Config::MAIN_USE_GAME_COVERS));
   m_checkbox_focused_hotkeys->setChecked(Config::Get(Config::MAIN_FOCUSED_HOTKEYS));
   m_checkbox_hide_mouse->setChecked(Settings::Instance().GetHideCursor());
+  m_checkbox_lock_mouse->setChecked(Settings::Instance().GetLockCursor());
   m_checkbox_disable_screensaver->setChecked(Config::Get(Config::MAIN_DISABLE_SCREENSAVER));
 }
 

diff --git a/Source/Core/DolphinQt/Settings/InterfacePane.h b/Source/Core/DolphinQt/Settings/InterfacePane.h
@@ -45,4 +45,5 @@ class InterfacePane final : public QWidget
   QCheckBox* m_checkbox_show_active_title;
   QCheckBox* m_checkbox_pause_on_focus_lost;
   QCheckBox* m_checkbox_hide_mouse;
+  QCheckBox* m_checkbox_lock_mouse;
 };
diff --git a/Source/DSPTool/StubHost.cpp b/Source/DSPTool/StubHost.cpp
@@ -39,6 +39,10 @@ bool Host_RendererHasFocus()
 {
   return false;
 }
+bool Host_RendererHasFullFocus()
+{
+  return false;
+}
 bool Host_RendererIsFullscreen()
 {
   return false;

diff --git a/Source/UnitTests/StubHost.cpp b/Source/UnitTests/StubHost.cpp
@@ -43,6 +43,10 @@ bool Host_RendererHasFocus()
 {
   return false;
 }
+bool Host_RendererHasFullFocus()
+{
+  return false;
+}
 bool Host_RendererIsFullscreen()
 {
   return false;