diff --git a/clang/lib/AST/TemplateBase.cpp b/clang/lib/AST/TemplateBase.cpp
index 0eef8f305fcb3..934e8f1f044f5 100644
--- a/clang/lib/AST/TemplateBase.cpp
+++ b/clang/lib/AST/TemplateBase.cpp
@@ -130,8 +130,14 @@ static void printIntegral(const TemplateArgument &TemplArg, raw_ostream &Out,
     } else
       Out << "(" << T->getCanonicalTypeInternal().getAsString(Policy) << ")"
           << Val;
-  } else
+  } else {
     Out << Val;
+    // Handle cases where the value is too large to fit into the underlying type
+    // i.e. where the unsignedness matters.
+    if (T->isBuiltinType())
+      if (Val.isUnsigned() && Val.getBitWidth() == 64 && Val.countLeadingOnes())
+        Out << "ULL";
+  }
 }
 
 static unsigned getArrayDepth(QualType type) {
diff --git a/clang/test/AST/ast-print-integral-template-args.cpp b/clang/test/AST/ast-print-integral-template-args.cpp
new file mode 100644
index 0000000000000..d1c26ca562ff0
--- /dev/null
+++ b/clang/test/AST/ast-print-integral-template-args.cpp
@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 -ast-print -std=c++17 -Wno-implicitly-unsigned-literal %s -o - | FileCheck %s
+
+template <unsigned long long N>
+struct Foo {};
+
+Foo<9223372036854775810> x;
+// CHECK: template<> struct Foo<9223372036854775810ULL> {