diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -158,6 +158,8 @@
       }
     }
 
+  - The ``-fexperimental-new-pass-manager`` and ``-fno-legacy-pass-manager``
+    flags have been removed. These have been no-ops since 15.0.0.
 
 What's New in Clang |release|?
 ==============================
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -2014,10 +2014,6 @@
   HelpText<"Enables the global instruction selector">;
 def fexperimental_isel : Flag<["-"], "fexperimental-isel">, Group<f_clang_Group>,
   Alias<fglobal_isel>;
-def fno_legacy_pass_manager : Flag<["-"], "fno-legacy-pass-manager">,
-  Group<f_clang_Group>, Flags<[CC1Option, NoArgumentUnused]>;
-def fexperimental_new_pass_manager : Flag<["-"], "fexperimental-new-pass-manager">,
-  Group<f_clang_Group>, Flags<[CC1Option]>, Alias<fno_legacy_pass_manager>;
 def fexperimental_strict_floating_point : Flag<["-"], "fexperimental-strict-floating-point">,
   Group<f_clang_Group>, Flags<[CC1Option]>,
   HelpText<"Enables experimental strict floating point in LLVM.">,
diff --git a/clang/test/Driver/flegacy-pass-manager.c b/clang/test/Driver/flegacy-pass-manager.c
deleted file mode 100644
--- a/clang/test/Driver/flegacy-pass-manager.c
+++ /dev/null
@@ -1,13 +0,0 @@
-/// -fno-legacy-pass-manager and -fexperimental-new-pass-manager are retained
-// as no-ops. The inverted options are no longer supported.
-
-// RUN: %clang -### -c -fno-legacy-pass-manager %s 2>&1 | FileCheck %s
-// RUN: not %clang -### -flegacy-pass-manager %s
-
-// RUN: %clang -### -c -fexperimental-new-pass-manager %s 2>&1 | FileCheck %s
-// RUN: not %clang -### -fno-experimental-new-pass-manager %s
-
-// Just check that there is no argument unused warning. There is no need to
-// pass any cc1 options.
-
-// CHECK-NOT: warning: argument unused