diff --git a/mybatis-flex-core/src/main/java/com/mybatisflex/core/BaseMapper.java b/mybatis-flex-core/src/main/java/com/mybatisflex/core/BaseMapper.java
index 25f4627b..ed04c9e4 100644
--- a/mybatis-flex-core/src/main/java/com/mybatisflex/core/BaseMapper.java
+++ b/mybatis-flex-core/src/main/java/com/mybatisflex/core/BaseMapper.java
@@ -500,6 +500,20 @@ public interface BaseMapper<T> {
         return MapperUtil.queryRelations(this, selectOneById(id));
     }
 
+    /**
+     * 根据主表主键来查询 1 条数据。
+     * @param id 表主键
+     * @param asType 接收数据类型
+     * @return 实体类数据
+     */
+    default <R> R selectOneWithRelationsByIdAs(Serializable id, Class<R> asType) {
+        try {
+            MappedStatementTypes.setCurrentType(asType);
+            return (R) selectOneWithRelationsById(id);
+        } finally {
+            MappedStatementTypes.clear();
+        }
+    }
     /**
      * 根据查询条件来查询 1 条数据。
      *