diff --git a/src/mzscheme/sconfig.h b/src/mzscheme/sconfig.h
index ae255b6001..f112e8a1de 100644
--- a/src/mzscheme/sconfig.h
+++ b/src/mzscheme/sconfig.h
@@ -260,9 +260,13 @@
   /************** x86/OpenBSD with gcc ****************/
               /* Thanks to Bengt Kleberg */
 
-# if defined(__OpenBSD__) && (defined(__i386__) || defined(i386))
+# if defined(__OpenBSD__) && (defined(__i386__) || defined(i386) || defined(__x86_64__))
 
+#if defined(__x86_64__)
+# define SCHEME_PLATFORM_LIBRARY_SUBPATH "x86_64-openbsd"
+#else
 # define SCHEME_PLATFORM_LIBRARY_SUBPATH "i386-openbsd"
+#endif
 
 # include "uconfig.h"
 # undef HAS_STANDARD_IOB
@@ -284,8 +288,13 @@
 
 # define USE_TM_GMTOFF_FIELD
 
+#if defined(__x86_64__)
+# define MZ_USE_JIT_X86_64
+# define MZ_JIT_USE_MPROTECT
+#else
 # define MZ_USE_JIT_I386
 # define MZ_JIT_USE_MPROTECT
+#endif
 
 # define FLAGS_ALREADY_SET