diff --git a/jerry-port/config-jupiter.h b/jerry-port/config-jupiter.h
index d9432e0c1b8641fd0839f51ae3693a6894c0c71a..f7efb0944cb5ceb6196e22d0daf0439d69adab64 100644
--- a/jerry-port/config-jupiter.h
+++ b/jerry-port/config-jupiter.h
@@ -30,7 +30,7 @@
 #define BMS_TASK_CONTEXT_AND_HEAP_SIZE (BMS_TASK_HEAP_SIZE + CONTEXT_SIZE_FOR_TASK)
 
 #ifndef JS_TASK_HEAP_SIZE
-#define JS_TASK_HEAP_SIZE (128)
+#define JS_TASK_HEAP_SIZE (64)
 #endif /* JS_TASK_HEAP_SIZE */
 
 // >= 51400 + (64-48) * 1024 + 8