diff --git a/src/leveldb/port/port_win.h b/src/leveldb/port/port_win.h
index 45bf2f0ea7..b4de4096cb 100644
--- a/src/leveldb/port/port_win.h
+++ b/src/leveldb/port/port_win.h
@@ -43,6 +43,11 @@
 #include <snappy.h>
 #endif
 
+#if defined(_MSC_VER)
+#include <BaseTsd.h>
+typedef SSIZE_T ssize_t;
+#endif
+
 namespace leveldb {
 namespace port {