diff --git a/clang/docs/LibASTMatchersReference.html b/clang/docs/LibASTMatchersReference.html
--- a/clang/docs/LibASTMatchersReference.html
+++ b/clang/docs/LibASTMatchersReference.html
@@ -5628,6 +5628,17 @@
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt;</td><td class="name" onclick="toggle('isConstinit0')"><a name="isConstinit0Anchor">isConstinit</a></td><td></td></tr>
+<tr><td colspan="4" class="doc" id="isConstinit0"><pre>Matches constinit variable declarations.
+
+Given:
+  constinit int foo = 42;
+  constinit const char* bar = "baz";
+varDecl(isConstinit())
+  matches the declaration of foo and bar.
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt;</td><td class="name" onclick="toggle('isDefinition1')"><a name="isDefinition1Anchor">isDefinition</a></td><td></td></tr>
 <tr><td colspan="4" class="doc" id="isDefinition1"><pre>Matches if a declaration has a body attached.
 
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -323,6 +323,8 @@
   underlying type.
 - Added the ``isConsteval`` matcher to match ``consteval`` function
   declarations as well as `if consteval` and `if ! consteval` statements.
+- Added the ``isConstinit`` matcher to match ``constinit`` variable
+  declarations.
 
 clang-format
 ------------
diff --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
--- a/clang/include/clang/ASTMatchers/ASTMatchers.h
+++ b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -5211,6 +5211,17 @@
   return Node.isConstexpr();
 }
 
+/// Matches constinit variable declarations.
+///
+/// Given:
+/// \code
+///   constinit int foo = 42;
+///   constinit const char* bar = "baz";
+/// \endcode
+/// varDecl(isConstinit())
+///   matches the declaration of foo and bar.
+AST_MATCHER(VarDecl, isConstinit) { return Node.hasAttr<ConstInitAttr>(); }
+
 /// Matches selection statements with initializer.
 ///
 /// Given:
diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -406,6 +406,7 @@
   REGISTER_MATCHER(isConstQualified);
   REGISTER_MATCHER(isConsteval);
   REGISTER_MATCHER(isConstexpr);
+  REGISTER_MATCHER(isConstinit);
   REGISTER_MATCHER(isCopyAssignmentOperator);
   REGISTER_MATCHER(isCopyConstructor);
   REGISTER_MATCHER(isDefaultConstructor);
diff --git a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
--- a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
@@ -1841,6 +1841,22 @@
       notMatches("void baz() { if (1 > 0) {} }", ifStmt(isConstexpr())));
 }
 
+TEST_P(ASTMatchersTest, IsConstinit) {
+  if (!GetParam().isCXX20OrLater())
+    return;
+
+  EXPECT_TRUE(matches("constinit int foo = 1;",
+                      varDecl(hasName("foo"), isConstinit())));
+  EXPECT_TRUE(matches("extern constinit int foo;",
+                      varDecl(hasName("foo"), isConstinit())));
+  EXPECT_TRUE(matches("constinit const char* foo = \"bar\";",
+                      varDecl(hasName("foo"), isConstinit())));
+  EXPECT_TRUE(notMatches("constexpr int foo = 1;",
+                         varDecl(hasName("foo"), isConstinit())));
+  EXPECT_TRUE(notMatches("static inline int foo = 1;",
+                         varDecl(hasName("foo"), isConstinit())));
+}
+
 TEST_P(ASTMatchersTest, HasInitStatement_MatchesSelectionInitializers) {
   EXPECT_TRUE(notMatches("void baz() { if (1 > 0) {} }",
                          ifStmt(hasInitStatement(anything()))));