diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 3915fb30a..5ad5497c7 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -1724,7 +1724,7 @@ void Tokenizer::simplifyNamespaces()
 {
     for (Token *token = _tokens; token; token = token->next())
     {
-        while (token && token->str() == "namespace" &&
+        while (token && token->str() == "namespace" && token->varId() == 0 &&
                (!token->previous() || token->previous()->str() != "using"))
         {
             // Token is namespace and there is no "using" before it.
diff --git a/test/testsimplifytokens.cpp b/test/testsimplifytokens.cpp
index 1ada1aab6..05909251b 100644
--- a/test/testsimplifytokens.cpp
+++ b/test/testsimplifytokens.cpp
@@ -1576,6 +1576,14 @@ private:
 
             ASSERT_EQUALS(expected, sizeof_(code));
         }
+
+        {
+            const char code[] = "void f(int namespace) { }";
+
+            const std::string expected("void f ( int namespace ) { }");
+
+            ASSERT_EQUALS(expected, sizeof_(code));
+        }
     }