diff --git a/src/os/unix/ngx_darwin_config.h b/src/os/unix/ngx_darwin_config.h
index 373ed14e3..39009768f 100644
--- a/src/os/unix/ngx_darwin_config.h
+++ b/src/os/unix/ngx_darwin_config.h
@@ -24,6 +24,7 @@
 #include <grp.h>
 #include <dirent.h>
 #include <glob.h>
+#include <sys/mount.h>          /* statfs() */
 
 #include <sys/filio.h>          /* FIONBIO */
 #include <sys/ioctl.h>