diff --git a/blade-service/blade-transport/src/main/java/org/springblade/transport/mapper/VehicleDispatchMapper.xml b/blade-service/blade-transport/src/main/java/org/springblade/transport/mapper/VehicleDispatchMapper.xml
index 72a9bfb..a5d3213 100644
--- a/blade-service/blade-transport/src/main/java/org/springblade/transport/mapper/VehicleDispatchMapper.xml
+++ b/blade-service/blade-transport/src/main/java/org/springblade/transport/mapper/VehicleDispatchMapper.xml
@@ -28,8 +28,8 @@
                d.is_deleted
         FROM blade_transport_vehicle_dispatch d
         LEFT JOIN blade_transport_vehicle v
-            ON v.plate_no = d.plate_no
-            AND v.tenant_id = d.tenant_id
+            ON v.plate_no COLLATE utf8mb4_general_ci = d.plate_no
+            AND v.tenant_id COLLATE utf8mb4_general_ci = d.tenant_id
             AND v.is_deleted = 0
         WHERE d.is_deleted = 0
         <if test="dispatch.applicationNo != null and dispatch.applicationNo != ''">
diff --git a/doc/sql/transport/blade_transport_vehicle.sql b/doc/sql/transport/blade_transport_vehicle.sql
index a5260fb..3a5f3f2 100644
--- a/doc/sql/transport/blade_transport_vehicle.sql
+++ b/doc/sql/transport/blade_transport_vehicle.sql
@@ -57,7 +57,7 @@ CREATE TABLE `blade_transport_vehicle` (
   KEY `idx_transport_vehicle_road_end` (`road_transport_cert_end_date`) USING BTREE,
   KEY `idx_transport_vehicle_annual_end` (`annual_review_end_date`) USING BTREE,
   KEY `idx_transport_vehicle_status` (`status`) USING BTREE
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='车辆管理';
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci COMMENT='车辆管理';
 
 -- ----------------------------
 -- Records of blade_menu for transport capacity vehicle
diff --git a/doc/sql/transport/blade_transport_vehicle_collation_20260923.sql b/doc/sql/transport/blade_transport_vehicle_collation_20260923.sql
new file mode 100644
index 0000000..a073370
--- /dev/null
+++ b/doc/sql/transport/blade_transport_vehicle_collation_20260923.sql
@@ -0,0 +1,4 @@
+-- 对齐车辆表字符串列排序规则，避免与 utf8mb4_general_ci 表 JOIN 报 Illegal mix of collations
+-- 背景：blade_transport_vehicle 建表未显式指定 COLLATE，MySQL 8 默认 utf8mb4_0900_ai_ci
+ALTER TABLE `blade_transport_vehicle`
+  CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;