diff --git a/bms-back/bms-system/src/main/java/com/bms/ar/domain/ArBillDetail.java b/bms-back/bms-system/src/main/java/com/bms/ar/domain/ArBillDetail.java
index eb3aa8b2..0243cf59 100644
--- a/bms-back/bms-system/src/main/java/com/bms/ar/domain/ArBillDetail.java
+++ b/bms-back/bms-system/src/main/java/com/bms/ar/domain/ArBillDetail.java
@@ -32,6 +32,8 @@ public class ArBillDetail implements Serializable {
     private String countryName;
     private String destPostcode;
     private BigDecimal actualWeight;
+    /** prc_order_bill.weight 来源快照。 */
+    private BigDecimal weight;
     private BigDecimal volumeWeight;
     private BigDecimal chargeWeight;
     /** 订单计费时命中的运费单价快照，对应 prc_order_bill.freight_rate。 */
diff --git a/bms-back/bms-system/src/main/java/com/bms/ar/service/impl/ArBillServiceImpl.java b/bms-back/bms-system/src/main/java/com/bms/ar/service/impl/ArBillServiceImpl.java
index 9edbb99f..38dd8b1b 100644
--- a/bms-back/bms-system/src/main/java/com/bms/ar/service/impl/ArBillServiceImpl.java
+++ b/bms-back/bms-system/src/main/java/com/bms/ar/service/impl/ArBillServiceImpl.java
@@ -1169,6 +1169,7 @@ public class ArBillServiceImpl implements IArBillService {
         detail.setCountryName(source.getCountryName());
         detail.setDestPostcode(source.getDestPostcode());
         detail.setActualWeight(source.getActualWeight());
+        detail.setWeight(source.getWeight());
         detail.setVolumeWeight(source.getVolumeWeight());
         detail.setChargeWeight(source.getChargeWeight() == null ? source.getWeight() : source.getChargeWeight());
         detail.setFreightRate(source.getFreightRate());
@@ -1496,7 +1497,7 @@ public class ArBillServiceImpl implements IArBillService {
                 detail.getOrderNo(), detail.getTrackingNo(),
                 StringUtils.isEmpty(detail.getProductName()) ? detail.getProductCode() : detail.getProductName(),
                 StringUtils.isEmpty(detail.getCountryName()) ? detail.getCountryCode() : detail.getCountryName(),
-                detail.getDestPostcode(), decimal(detail.getActualWeight(), 3), decimal(detail.getPkgLength(), 2),
+                detail.getDestPostcode(), decimal(detail.getWeight(), 3), decimal(detail.getPkgLength(), 2),
                 decimal(detail.getPkgHeight(), 2), decimal(detail.getPkgWidth(), 2), decimal(detail.getVolumeWeight(), 3),
                 decimal(detail.getChargeWeight(), 3), exportUnitPrice(detail), exportProcessingFee(detail),
                 exportFormula(detail), exportFeeType(), detail.getCurrency(), detail.getTotalAmount(), exportRemark(detail)
diff --git a/bms-back/bms-system/src/main/resources/mapper/ar/ArBillDetailMapper.xml b/bms-back/bms-system/src/main/resources/mapper/ar/ArBillDetailMapper.xml
index 63962f7f..8f107e72 100644
--- a/bms-back/bms-system/src/main/resources/mapper/ar/ArBillDetailMapper.xml
+++ b/bms-back/bms-system/src/main/resources/mapper/ar/ArBillDetailMapper.xml
@@ -20,6 +20,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
         <result property="countryName" column="country_name"/>
         <result property="destPostcode" column="dest_postcode"/>
         <result property="actualWeight" column="actual_weight"/>
+        <result property="weight" column="weight"/>
         <result property="volumeWeight" column="volume_weight"/>
         <result property="chargeWeight" column="charge_weight"/>
         <result property="freightRate" column="freight_rate"/>
@@ -39,7 +40,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
     <select id="selectByBillId" parameterType="long" resultMap="ArBillDetailResult">
         select detail_id, ar_bill_id, prc_order_bill_id, detail_no, order_no, tracking_no, transfer_no, receive_time,
                product_code, product_name, goods_description, country_code, country_name, dest_postcode,
-               actual_weight, volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height,
+               actual_weight, weight, volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height,
                currency, total_amount, product_amount, redline_amount, remark, create_by, create_time
         from ar_bill_detail where ar_bill_id = #{arBillId} order by detail_no
     </select>
@@ -47,7 +48,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
     <select id="selectByBillIdAndSourceIds" resultMap="ArBillDetailResult">
         select detail_id, ar_bill_id, prc_order_bill_id, detail_no, order_no, tracking_no, transfer_no, receive_time,
                product_code, product_name, goods_description, country_code, country_name, dest_postcode,
-               actual_weight, volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height,
+               actual_weight, weight, volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height,
                currency, total_amount, product_amount, redline_amount, remark, create_by, create_time
         from ar_bill_detail
         where ar_bill_id = #{arBillId}
@@ -85,7 +86,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
     <select id="selectByBillIdWithFees" parameterType="long" resultMap="ArBillDetailWithFeesResult">
         select d.detail_id, d.ar_bill_id, d.prc_order_bill_id, d.detail_no, d.order_no, d.tracking_no, d.transfer_no, d.receive_time,
                d.product_code, d.product_name, d.goods_description, d.country_code, d.country_name, d.dest_postcode,
-               d.actual_weight, d.volume_weight, d.charge_weight, d.freight_rate, d.registration_fee, d.pkg_length, d.pkg_width, d.pkg_height,
+               d.actual_weight, d.weight, d.volume_weight, d.charge_weight, d.freight_rate, d.registration_fee, d.pkg_length, d.pkg_width, d.pkg_height,
                d.currency, d.total_amount, d.product_amount, d.redline_amount, d.remark, d.create_by, d.create_time,
                f.detail_fee_id as fee_detail_id, f.detail_id as fee_parent_detail_id,
                f.prc_income_bill_fee_id as fee_prc_income_bill_fee_id,
@@ -104,7 +105,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
     <select id="selectExportPage" resultMap="ArBillDetailResult">
         select detail_id, ar_bill_id, prc_order_bill_id, detail_no, order_no, tracking_no, transfer_no, receive_time,
                product_code, product_name, goods_description, country_code, country_name, dest_postcode,
-               actual_weight, volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height,
+               actual_weight, weight, volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height,
                currency, total_amount, product_amount, redline_amount, remark, create_by, create_time
         from ar_bill_detail
         where ar_bill_id = #{arBillId} and detail_no &gt; #{lastDetailNo}
@@ -122,20 +123,20 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
         insert into ar_bill_detail (ar_bill_id, prc_order_bill_id, detail_no, order_no, tracking_no, transfer_no, receive_time,
                                     product_code,
                                     product_name, goods_description, country_code, country_name, dest_postcode,
-                                    actual_weight,
+                                    actual_weight, weight,
                                     volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height, currency,
                                     total_amount, product_amount, redline_amount,
                                     remark, create_by, create_time)
         values (#{arBillId}, #{prcOrderBillId}, #{detailNo}, #{orderNo}, #{trackingNo}, #{transferNo}, #{receiveTime},
                 #{productCode}, #{productName}, #{goodsDescription}, #{countryCode}, #{countryName},
-                #{destPostcode}, #{actualWeight}, #{volumeWeight}, #{chargeWeight}, #{freightRate}, #{registrationFee}, #{pkgLength}, #{pkgWidth},
+                #{destPostcode}, #{actualWeight}, #{weight}, #{volumeWeight}, #{chargeWeight}, #{freightRate}, #{registrationFee}, #{pkgLength}, #{pkgWidth},
                 #{pkgHeight}, #{currency}, #{totalAmount}, #{productAmount}, #{redlineAmount}, #{remark}, #{createBy}, sysdate())
     </insert>
 
     <insert id="insertBatch" parameterType="java.util.List" useGeneratedKeys="true" keyProperty="detailId">
         insert into ar_bill_detail (
             ar_bill_id, prc_order_bill_id, detail_no, order_no, tracking_no, transfer_no, receive_time, product_code,
-            product_name, goods_description, country_code, country_name, dest_postcode, actual_weight,
+            product_name, goods_description, country_code, country_name, dest_postcode, actual_weight, weight,
             volume_weight, charge_weight, freight_rate, registration_fee, pkg_length, pkg_width, pkg_height, currency, total_amount,
             product_amount, redline_amount,
             remark, create_by, create_time
@@ -143,7 +144,7 @@ PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
         <foreach collection="list" item="item" separator=",">
             (#{item.arBillId}, #{item.prcOrderBillId}, #{item.detailNo}, #{item.orderNo}, #{item.trackingNo},
              #{item.transferNo}, #{item.receiveTime}, #{item.productCode}, #{item.productName}, #{item.goodsDescription},
-             #{item.countryCode}, #{item.countryName}, #{item.destPostcode}, #{item.actualWeight},
+             #{item.countryCode}, #{item.countryName}, #{item.destPostcode}, #{item.actualWeight}, #{item.weight},
              #{item.volumeWeight}, #{item.chargeWeight}, #{item.freightRate}, #{item.registrationFee}, #{item.pkgLength}, #{item.pkgWidth}, #{item.pkgHeight},
              #{item.currency}, #{item.totalAmount}, #{item.productAmount}, #{item.redlineAmount},
              #{item.remark}, #{item.createBy}, sysdate())
diff --git a/bms-back/sql/20261012_add_ar_bill_detail_weight_from_order.sql b/bms-back/sql/20261012_add_ar_bill_detail_weight_from_order.sql
new file mode 100644
index 00000000..c7a7428e
--- /dev/null
+++ b/bms-back/sql/20261012_add_ar_bill_detail_weight_from_order.sql
@@ -0,0 +1,21 @@
+-- 应收账单订单明细冗余 prc_order_bill.weight，供账单导出使用。
+-- 来源字段为空时快照保留 NULL，不伪造为 0。
+
+SET @column_exists := (
+  SELECT COUNT(1) FROM information_schema.COLUMNS
+  WHERE TABLE_SCHEMA = DATABASE()
+    AND TABLE_NAME = 'ar_bill_detail'
+    AND COLUMN_NAME = 'weight'
+);
+SET @sql := IF(@column_exists = 0,
+  'ALTER TABLE `ar_bill_detail` ADD COLUMN `weight` decimal(10,3) DEFAULT NULL COMMENT ''prc_order_bill.weight来源快照'' AFTER `actual_weight`',
+  'SELECT 1'
+);
+PREPARE stmt FROM @sql;
+EXECUTE stmt;
+DEALLOCATE PREPARE stmt;
+
+UPDATE `ar_bill_detail` d
+INNER JOIN `prc_order_bill` p ON p.`bill_id` = d.`prc_order_bill_id`
+SET d.`weight` = p.`weight`
+WHERE d.`weight` IS NULL AND p.`weight` IS NOT NULL;
diff --git a/bms-back/sql/bms_init.sql b/bms-back/sql/bms_init.sql
index 868498f9..c66c5924 100644
--- a/bms-back/sql/bms_init.sql
+++ b/bms-back/sql/bms_init.sql
@@ -116,6 +116,7 @@ CREATE TABLE `ar_bill_detail` (
   `country_name` varchar(50) COLLATE utf8mb4_unicode_ci DEFAULT NULL COMMENT '目的国家名称',
   `dest_postcode` varchar(20) COLLATE utf8mb4_unicode_ci DEFAULT NULL COMMENT '目的邮编',
   `actual_weight` decimal(12,3) DEFAULT NULL COMMENT '实际重量KG',
+  `weight` decimal(10,3) DEFAULT NULL COMMENT 'prc_order_bill.weight来源快照',
   `volume_weight` decimal(12,3) DEFAULT NULL COMMENT '材积重量KG',
   `charge_weight` decimal(12,3) DEFAULT NULL COMMENT '计费重量KG',
   `freight_rate` decimal(10,4) DEFAULT NULL COMMENT '运费单价快照',