diff --git a/common/file_util.cc b/common/file_util.cc
index db4aad2..618ffc0 100644
--- a/common/file_util.cc
+++ b/common/file_util.cc
@@ -17,6 +17,7 @@
 #include <cstring>
 #include <fstream>
 #include <ios>
+#include <string>
 
 namespace libwebm {