diff --git a/src/flib/pio.F90 b/src/flib/pio.F90
index 44d3fbc92ff..7cc30824b3d 100644
--- a/src/flib/pio.F90
+++ b/src/flib/pio.F90
@@ -7,7 +7,7 @@
 !>
 !! @defgroup PIO_set_blocksize Box Rearranger Settings
 !! Set the box rearranger blocksize in Fortran.
-#include 'config.h'
+#include "config.h"
 
 module pio
 ! Package all exposed variables and functions under one roof