diff --git a/src/slimit/lexer.py b/src/slimit/lexer.py
index 06cd7c5..33dc93e 100644
--- a/src/slimit/lexer.py
+++ b/src/slimit/lexer.py
@@ -25,6 +25,7 @@
 __author__ = 'Ruslan Spivak <ruslan.spivak@gmail.com>'
 
 import ply.lex
+import logging
 
 from slimit.unicode_chars import (
     LETTER,
@@ -432,6 +433,6 @@ def t_ID(self, token):
         return token
 
     def t_error(self, token):
-        print 'Illegal character %r at %s:%s after %s' % (
-            token.value[0], token.lineno, token.lexpos, self.prev_token)
+        logging.debug('Illegal character %r at %s:%s after %s' % (
+            token.value[0], token.lineno, token.lexpos, self.prev_token))
         token.lexer.skip(1)