diff --git a/news/305.new.rst b/news/305.new.rst
new file mode 100644
index 00000000..601997cf
--- /dev/null
+++ b/news/305.new.rst
@@ -0,0 +1 @@
+Add a hook for ``qtmodern`` to collect qss data files.
diff --git a/requirements-test-libraries.txt b/requirements-test-libraries.txt
index 8ff6600b..c71c3e04 100644
--- a/requirements-test-libraries.txt
+++ b/requirements-test-libraries.txt
@@ -32,6 +32,8 @@ pyusb==1.0.2
 pynput==1.7.3
 pystray==0.17.3
 pyzmq==22.0.3
+PyQt5==5.15.4
+qtmodern==0.2.0
 Rtree==0.9.7
 sentry-sdk==0.19.3
 # shotgun_api3 can only be installed from git
diff --git a/src/_pyinstaller_hooks_contrib/hooks/stdhooks/hook-qtmodern.py b/src/_pyinstaller_hooks_contrib/hooks/stdhooks/hook-qtmodern.py
new file mode 100644
index 00000000..316b16d3
--- /dev/null
+++ b/src/_pyinstaller_hooks_contrib/hooks/stdhooks/hook-qtmodern.py
@@ -0,0 +1,15 @@
+# ------------------------------------------------------------------
+# Copyright (c) 2021 PyInstaller Development Team.
+#
+# This file is distributed under the terms of the GNU General Public
+# License (version 2.0 or later).
+#
+# The full license is available in LICENSE.GPL.txt, distributed with
+# this software.
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+# ------------------------------------------------------------------
+
+from PyInstaller.utils.hooks import collect_data_files
+
+datas = collect_data_files("qtmodern", includes=["**/*.qss"])
diff --git a/src/_pyinstaller_hooks_contrib/tests/test_libraries.py b/src/_pyinstaller_hooks_contrib/tests/test_libraries.py
index 4fb2cd5c..f3145daa 100644
--- a/src/_pyinstaller_hooks_contrib/tests/test_libraries.py
+++ b/src/_pyinstaller_hooks_contrib/tests/test_libraries.py
@@ -738,3 +738,29 @@ def test_pythonnet3(pyi_builder):
 
         import clr
         """)
+
+
+if is_win:
+    # This is a hack to prevent monkeypatch from interfering with PyQt5's additional PATH entries. See:
+    # https://github.com/pyinstaller/pyinstaller/commit/b66c9021129e9e875ddd138a298ce542483dd6c9
+    try:
+        import PyQt5  # noqa: F401
+    except ImportError:
+        pass
+
+
+@importorskip("qtmodern")
+@importorskip("PyQt5")
+def test_qtmodern(pyi_builder):
+    pyi_builder.test_source("""
+        import sys
+        from PyQt5 import QtWidgets
+        import qtmodern.styles
+        import qtmodern.windows
+
+        app = QtWidgets.QApplication(sys.argv)
+        window = QtWidgets.QWidget()
+        qtmodern.styles.dark(app)
+        modern_window = qtmodern.windows.ModernWindow(window)
+        modern_window.show()
+        """)