diff --git a/src/google/protobuf/compiler/parser.cc b/src/google/protobuf/compiler/parser.cc
index 5d45741c67145..e12642610252a 100644
--- a/src/google/protobuf/compiler/parser.cc
+++ b/src/google/protobuf/compiler/parser.cc
@@ -1793,10 +1793,11 @@ bool Parser::ParseReservedName(std::string* name,
   int col = input_->current().column;
   DO(ConsumeString(name, error_message));
   if (!io::Tokenizer::IsIdentifier(*name)) {
-    RecordWarning(
+    RecordError(
         line, col,
         absl::StrFormat("Reserved name \"%s\" is not a valid identifier.",
                         *name));
+    return false;
   }
   return true;
 }
diff --git a/src/google/protobuf/compiler/parser_unittest.cc b/src/google/protobuf/compiler/parser_unittest.cc
index 3c16aad4c8e76..888d65dfb7548 100644
--- a/src/google/protobuf/compiler/parser_unittest.cc
+++ b/src/google/protobuf/compiler/parser_unittest.cc
@@ -1745,7 +1745,7 @@ TEST_F(ParseErrorTest, EnumReservedMissingQuotes) {
 }
 
 TEST_F(ParseErrorTest, EnumReservedInvalidIdentifier) {
-  ExpectHasWarnings(
+  ExpectHasErrors(
       R"pb(
       enum TestEnum {
         FOO = 1;
@@ -1783,7 +1783,7 @@ TEST_F(ParseErrorTest, ReservedMissingQuotes) {
 }
 
 TEST_F(ParseErrorTest, ReservedInvalidIdentifier) {
-  ExpectHasWarnings(
+  ExpectHasErrors(
       R"pb(
       message Foo {
         reserved "foo bar";