diff --git a/include/neuron/define.h b/include/neuron/define.h
index 48e277611..7a027bce3 100644
--- a/include/neuron/define.h
+++ b/include/neuron/define.h
@@ -33,7 +33,7 @@
 
 #define NEU_TAG_NAME_LEN 128
 #define NEU_TAG_ADDRESS_LEN 128
-#define NEU_TAG_DESCRIPTION_LEN 128
+#define NEU_TAG_DESCRIPTION_LEN 256
 #define NEU_GROUP_MAX_PER_NODE 512
 #define NEU_GROUP_NAME_LEN 128
 #define NEU_GROUP_INTERVAL_LIMIT 100