diff --git a/pytest-profiling/pytest_profiling.py b/pytest-profiling/pytest_profiling.py
index 746bfc15..9917b6f5 100644
--- a/pytest-profiling/pytest_profiling.py
+++ b/pytest-profiling/pytest_profiling.py
@@ -17,7 +17,7 @@
 
 
 def clean_filename(s):
-    forbidden_chars = set('/?<>\:*|"')
+    forbidden_chars = set(r'/?<>\:*|"')
     return six.text_type("".join(c if c not in forbidden_chars and ord(c) < 127 else '_'
                                  for c in s))