diff --git a/sqlparse/sql.py b/sqlparse/sql.py
index 8b530bdf..37aa3bb4 100644
--- a/sqlparse/sql.py
+++ b/sqlparse/sql.py
@@ -149,7 +149,7 @@ def __init__(self, tokens=None):
         super(TokenList, self).__init__(None, text_type(self))
 
     def __str__(self):
-        return ''.join(token.value for token in self.flatten())
+        return ''.join(token.value for token in self.tokens)
 
     # weird bug
     # def __len__(self):