diff --git a/llvm/include/llvm/IR/LegacyPassManager.h b/llvm/include/llvm/IR/LegacyPassManager.h
index 2b87143276b9a..2459f0a5450a0 100644
--- a/llvm/include/llvm/IR/LegacyPassManager.h
+++ b/llvm/include/llvm/IR/LegacyPassManager.h
@@ -26,6 +26,10 @@ class Module;
 
 namespace legacy {
 
+// Whether or not -debug-pass has been specified. For use to check if it's
+// specified alongside the new PM.
+bool debugPassSpecified();
+
 class PassManagerImpl;
 class FunctionPassManagerImpl;
 
diff --git a/llvm/lib/IR/LegacyPassManager.cpp b/llvm/lib/IR/LegacyPassManager.cpp
index 94be208617c50..32840fdeddf79 100644
--- a/llvm/lib/IR/LegacyPassManager.cpp
+++ b/llvm/lib/IR/LegacyPassManager.cpp
@@ -242,6 +242,8 @@ void PassManagerPrettyStackEntry::print(raw_ostream &OS) const {
 
 namespace llvm {
 namespace legacy {
+bool debugPassSpecified() { return PassDebugging != Disabled; }
+
 //===----------------------------------------------------------------------===//
 // FunctionPassManagerImpl
 //
diff --git a/llvm/test/Other/debug-pass-npm.ll b/llvm/test/Other/debug-pass-npm.ll
new file mode 100644
index 0000000000000..55c9baa6c5732
--- /dev/null
+++ b/llvm/test/Other/debug-pass-npm.ll
@@ -0,0 +1,4 @@
+; RUN: opt -enable-new-pm=0 -O1 %s -debug-pass=Structure
+; RUN: not opt -enable-new-pm=1 -O1 %s -debug-pass=Structure 2>&1 | FileCheck %s
+
+; CHECK: does not work
diff --git a/llvm/tools/opt/opt.cpp b/llvm/tools/opt/opt.cpp
index 48b0e397c9802..f690d5f1a789b 100644
--- a/llvm/tools/opt/opt.cpp
+++ b/llvm/tools/opt/opt.cpp
@@ -775,6 +775,12 @@ int main(int argc, char **argv) {
                 "full list of passes, see the '--print-passes' flag.\n";
       return 1;
     }
+    if (legacy::debugPassSpecified()) {
+      errs()
+          << "-debug-pass does not work with the new PM, either use "
+             "-debug-pass-manager, or use the legacy PM (-enable-new-pm=0)\n";
+      return 1;
+    }
     if (PassPipeline.getNumOccurrences() > 0 && PassList.size() > 0) {
       errs()
           << "Cannot specify passes via both -foo-pass and --passes=foo-pass\n";