diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp
index 239280c652556..4fcc640d90716 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp
@@ -56,6 +56,7 @@
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclObjC.h"
 
+#include "clang/Basic/DiagnosticSema.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/ScopeExit.h"
 #include "llvm/BinaryFormat/Dwarf.h"
@@ -988,9 +989,33 @@ void ClangUserExpression::FixupCVRParseErrorDiagnostics(
       !m_fixed_text.empty() ? m_fixed_text.c_str() : m_expr_text.c_str());
 }
 
+void ClangUserExpression::FixupTemplateLookupDiagnostics(
+    DiagnosticManager &diagnostic_manager) const {
+  if (llvm::none_of(diagnostic_manager.Diagnostics(),
+                    [](std::unique_ptr<Diagnostic> const &diag) {
+                      switch (diag->GetCompilerID()) {
+                      // FIXME: should we also be checking
+                      // clang::diag::err_no_member_template?
+                      case clang::diag::err_no_template:
+                      case clang::diag::err_non_template_in_template_id:
+                        return true;
+                      default:
+                        return false;
+                      }
+                    }))
+    return;
+
+  diagnostic_manager.AddDiagnostic(
+      "Naming template instantiation not yet supported. Template functions "
+      "can be invoked via their mangled name. For example, using "
+      "`_Z3fooIiEvi(123)` for `foo<int>(123)`",
+      lldb::eSeverityInfo, eDiagnosticOriginLLDB);
+}
+
 void ClangUserExpression::FixupParseErrorDiagnostics(
     DiagnosticManager &diagnostic_manager) const {
   FixupCVRParseErrorDiagnostics(diagnostic_manager);
+  FixupTemplateLookupDiagnostics(diagnostic_manager);
 }
 
 char ClangUserExpression::ClangUserExpressionHelper::ID;
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.h b/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.h
index fd24893b1ecdd..74aceed1d637e 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.h
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.h
@@ -215,6 +215,9 @@ class ClangUserExpression : public LLVMUserExpression {
   void
   FixupCVRParseErrorDiagnostics(DiagnosticManager &diagnostic_manager) const;
 
+  void
+  FixupTemplateLookupDiagnostics(DiagnosticManager &diagnostic_manager) const;
+
   /// Defines how the current expression should be wrapped.
   ClangExpressionSourceCode::WrapKind GetWrapKind() const;
   bool SetupPersistentState(DiagnosticManager &diagnostic_manager,
diff --git a/lldb/test/API/lang/cpp/template-diagnostic-hint/Makefile b/lldb/test/API/lang/cpp/template-diagnostic-hint/Makefile
new file mode 100644
index 0000000000000..99998b20bcb05
--- /dev/null
+++ b/lldb/test/API/lang/cpp/template-diagnostic-hint/Makefile
@@ -0,0 +1,3 @@
+CXX_SOURCES := main.cpp
+
+include Makefile.rules
diff --git a/lldb/test/API/lang/cpp/template-diagnostic-hint/TestTemplateDiagnosticHint.py b/lldb/test/API/lang/cpp/template-diagnostic-hint/TestTemplateDiagnosticHint.py
new file mode 100644
index 0000000000000..e8287108f7583
--- /dev/null
+++ b/lldb/test/API/lang/cpp/template-diagnostic-hint/TestTemplateDiagnosticHint.py
@@ -0,0 +1,48 @@
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+
+class TestCase(TestBase):
+    def test(self):
+        self.build()
+        (_, process, _, _) = lldbutil.run_to_source_breakpoint(
+            self, "main", lldb.SBFileSpec("main.cpp")
+        )
+
+        self.expect(
+            "expression some_template_func<int, long>(5)",
+            error=True,
+            substrs=[
+                "does not name a template but is followed by template arguments",
+                "note: Naming template instantiation not yet supported.",
+                "Template functions can be invoked via their mangled name.",
+            ],
+        )
+
+        self.expect(
+            "expression some_template_func<int, long>(5) + some_template_func<int, long>(5)",
+            error=True,
+            substrs=[
+                "does not name a template but is followed by template arguments",
+                "does not name a template but is followed by template arguments",
+            ],
+        )
+
+        self.assertEqual(
+            self.res.GetError().count(
+                "note: Naming template instantiation not yet supported"
+            ),
+            1,
+        )
+
+        self.expect(
+            "expression Foo<int>::smethod()",
+            error=True,
+            substrs=[
+                "no template named 'Foo'",
+                "note: Naming template instantiation not yet supported.",
+                "Template functions can be invoked via their mangled name.",
+            ],
+        )
diff --git a/lldb/test/API/lang/cpp/template-diagnostic-hint/main.cpp b/lldb/test/API/lang/cpp/template-diagnostic-hint/main.cpp
new file mode 100644
index 0000000000000..914d9b59484de
--- /dev/null
+++ b/lldb/test/API/lang/cpp/template-diagnostic-hint/main.cpp
@@ -0,0 +1,14 @@
+template <typename T, typename K> static K some_template_func(int x) {
+  return (K)x;
+}
+
+template <typename T> struct Foo {
+  template <typename K> T method(K k) { return (T)k; }
+  static T smethod() { return (T)10; }
+};
+
+int main() {
+  Foo<int> f;
+  return some_template_func<int, long>(5) + Foo<int>::smethod() +
+         f.method<long>(10);
+}