diff --git a/viewsh-module-iot/viewsh-module-iot-gateway/src/main/java/com/viewsh/module/iot/gateway/codec/jt808/Jt808Decoder.java b/viewsh-module-iot/viewsh-module-iot-gateway/src/main/java/com/viewsh/module/iot/gateway/codec/jt808/Jt808Decoder.java
index a583301..b6ae4fd 100644
--- a/viewsh-module-iot/viewsh-module-iot-gateway/src/main/java/com/viewsh/module/iot/gateway/codec/jt808/Jt808Decoder.java
+++ b/viewsh-module-iot/viewsh-module-iot-gateway/src/main/java/com/viewsh/module/iot/gateway/codec/jt808/Jt808Decoder.java
@@ -56,18 +56,16 @@ public class Jt808Decoder {
             return ret;
         }
 
-        if (expectedBodyLength > actualAvailableLength) {
-            log.warn("[bytes2PackageData][消息体长度不匹配: 头部声明={}, 实际可用={}, 数据总长度={}, 消息ID=0x{}]",
-                    expectedBodyLength, actualAvailableLength, data.length,
+        // 使用实际可用的长度处理（兼容设备端长度计算不准确的情况）
+        int actualBodyLength = Math.min(expectedBodyLength, actualAvailableLength);
+        if (expectedBodyLength != actualAvailableLength) {
+            log.debug("[bytes2PackageData][消息体长度差异: 头部声明={}, 实际可用={}, 使用={}, 消息ID=0x{}]",
+                    expectedBodyLength, actualAvailableLength, actualBodyLength,
                     Integer.toHexString(msgHeader.getId()));
-            // 使用 null 标记长度不匹配（区别于合法的空消息体如心跳）
-            ret.setBodyBytes(null);
-            ret.setCheckSum(data[data.length - 1]);
-            return ret;
         }
 
-        byte[] bodyBytes = new byte[msgHeader.getBodyLength()];
-        System.arraycopy(data, msgBodyByteStartIndex, bodyBytes, 0, bodyBytes.length);
+        byte[] bodyBytes = new byte[actualBodyLength];
+        System.arraycopy(data, msgBodyByteStartIndex, bodyBytes, 0, actualBodyLength);
         ret.setBodyBytes(bodyBytes);
 
         // 3. 解析校验码