diff --git a/icu4c/source/test/intltest/bidiconf.cpp b/icu4c/source/test/intltest/bidiconf.cpp
index d4bdf716cd..0b4329f882 100644
--- a/icu4c/source/test/intltest/bidiconf.cpp
+++ b/icu4c/source/test/intltest/bidiconf.cpp
@@ -17,6 +17,7 @@
 */
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include "unicode/utypes.h"
 #include "unicode/ubidi.h"