diff --git a/ports/zephyr/mpconfigport.h b/ports/zephyr/mpconfigport.h
index e963e0d85897..26465cbb59b8 100644
--- a/ports/zephyr/mpconfigport.h
+++ b/ports/zephyr/mpconfigport.h
@@ -90,7 +90,7 @@
 #define MICROPY_PY_ZEPHYR           (1)
 #define MICROPY_PY_ZSENSOR          (1)
 #define MICROPY_PY_SYS_MODULES      (0)
-#define MICROPY_LONGINT_IMPL (MICROPY_LONGINT_IMPL_LONGLONG)
+#define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_MPZ)
 #define MICROPY_FLOAT_IMPL (MICROPY_FLOAT_IMPL_FLOAT)
 #define MICROPY_PY_BUILTINS_COMPLEX (0)
 #define MICROPY_ENABLE_SCHEDULER    (1)