diff --git a/app/lora/lora_mesh_uart_passthrough_manager.py b/app/lora/lora_mesh_uart_passthrough_manager.py
index 7387b96..f2f79e4 100644
--- a/app/lora/lora_mesh_uart_passthrough_manager.py
+++ b/app/lora/lora_mesh_uart_passthrough_manager.py
@@ -136,9 +136,8 @@ class LoRaMeshUartPassthroughManager:
 
             # 2.3 检查包是否完整
             payload_len = self._rx_buffer[1]
-            # 这里的 total_packet_len 计算方式存疑，它假设 payload_len 是 length 字段之后所有数据的长度。
-            # 这与 send_packet 中的 length 计算方式可能不一致。
-            total_packet_len = 1 + 1 + payload_len
+            # 物理层在末尾又加了2字节的源地址，所以完整包长需要+2。
+            total_packet_len = 1 + 1 + payload_len + 2
             log(f"LoRa: 帧头正确(ED)。声明的后续包长(payload_len): {payload_len}。计算出的总包长: {total_packet_len}。")
 
             if len(self._rx_buffer) < total_packet_len: