diff --git a/infra/packet_manager/packet_parser.c b/infra/packet_manager/packet_parser.c
index e4de9f5..76c4706 100644
--- a/infra/packet_manager/packet_parser.c
+++ b/infra/packet_manager/packet_parser.c
@@ -819,30 +819,44 @@ static inline const char *parse_gtp_u(struct packet *pkt, const char *data, uint
         return data;
     }
 
-    uint8_t next_proto = (((const uint8_t *)(data + hdr_len))[0]) >> 4;
-    if (next_proto != 4 && next_proto != 6)
+    if (hdr_len == len)
     {
-        // next_proto is not IPv4 or IPv6, this is not a normal GTP-U packet, fallback to UDP
-        return data;
-    }
-
-    struct layer_private *layer = get_free_layer(pkt);
-    if (unlikely(layer == NULL))
-    {
-        return data;
-    }
-    SET_LAYER(pkt, layer, LAYER_PROTO_GTP_U, hdr_len, data, len, 0);
-
-    switch (next_proto)
-    {
-    case 4:
-        return parse_ipv4(pkt, layer->pld_ptr, layer->pld_len);
-    case 6:
-        return parse_ipv6(pkt, layer->pld_ptr, layer->pld_len);
-    default:
-        PACKET_LOG_UNSUPPORT_PROTO(pkt, LAYER_PROTO_GTP_U, next_proto);
+        // only GTP-U header, no payload
+        struct layer_private *layer = get_free_layer(pkt);
+        if (unlikely(layer == NULL))
+        {
+            return data;
+        }
+        SET_LAYER(pkt, layer, LAYER_PROTO_GTP_U, hdr_len, data, len, 0);
         return layer->pld_ptr;
     }
+    else
+    {
+        uint8_t next_proto = (((const uint8_t *)(data + hdr_len))[0]) >> 4;
+        if (next_proto != 4 && next_proto != 6)
+        {
+            // next_proto is not IPv4 or IPv6, this is not a normal GTP-U packet, fallback to UDP
+            return data;
+        }
+
+        struct layer_private *layer = get_free_layer(pkt);
+        if (unlikely(layer == NULL))
+        {
+            return data;
+        }
+        SET_LAYER(pkt, layer, LAYER_PROTO_GTP_U, hdr_len, data, len, 0);
+
+        switch (next_proto)
+        {
+        case 4:
+            return parse_ipv4(pkt, layer->pld_ptr, layer->pld_len);
+        case 6:
+            return parse_ipv6(pkt, layer->pld_ptr, layer->pld_len);
+        default:
+            PACKET_LOG_UNSUPPORT_PROTO(pkt, LAYER_PROTO_GTP_U, next_proto);
+            return layer->pld_ptr;
+        }
+    }
 }
 
 static inline const char *parse_gtp_c(struct packet *pkt, const char *data, uint16_t len)