diff --git a/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/CustomKeyGenerator.java b/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/CustomKeyGenerator.java
index 1cdd00ab..da46f386 100644
--- a/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/CustomKeyGenerator.java
+++ b/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/CustomKeyGenerator.java
@@ -22,6 +22,7 @@ import com.mybatisflex.core.exception.FlexExceptions;
 import com.mybatisflex.core.table.IdInfo;
 import com.mybatisflex.core.table.TableInfo;
 import com.mybatisflex.core.util.ConvertUtil;
+import com.mybatisflex.core.util.StringUtil;
 import org.apache.ibatis.executor.Executor;
 import org.apache.ibatis.executor.ExecutorException;
 import org.apache.ibatis.executor.keygen.KeyGenerator;
@@ -71,17 +72,18 @@ public class CustomKeyGenerator implements KeyGenerator {
         Object entity = ((Map) parameter).get(FlexConsts.ENTITY);
         try {
             Object existId = tableInfo.getValue(entity, idInfo.getProperty());
+
             // 若用户主动设置了主键，则使用用户自己设置的主键，不再生成主键
-            if (existId != null){
-                return;
+            // 只有主键为 null 或者 空字符串时，对主键进行设置
+            if (existId == null || (existId instanceof String && StringUtil.isBlank((String) existId))) {
+                Configuration configuration = ms.getConfiguration();
+                MetaObject metaParam = configuration.newMetaObject(parameter);
+                Object generateId = keyGenerator.generate(entity, idInfo.getColumn());
+                MetaObject metaObjectForProperty = metaParam.metaObjectForProperty(FlexConsts.ENTITY);
+                Invoker setInvoker = tableInfo.getReflector().getSetInvoker(idInfo.getProperty());
+                Object id = ConvertUtil.convert(generateId, setInvoker.getType());
+                this.setValue(metaObjectForProperty, this.idInfo.getProperty(), id);
             }
-            Configuration configuration = ms.getConfiguration();
-            MetaObject metaParam = configuration.newMetaObject(parameter);
-            Object generateId = keyGenerator.generate(entity, idInfo.getColumn());
-            MetaObject metaObjectForProperty = metaParam.metaObjectForProperty(FlexConsts.ENTITY);
-            Invoker setInvoker = tableInfo.getReflector().getSetInvoker(idInfo.getProperty());
-            Object id = ConvertUtil.convert(generateId, setInvoker.getType());
-            this.setValue(metaObjectForProperty, this.idInfo.getProperty(), id);
         } catch (Exception e) {
             throw FlexExceptions.wrap(e);
         }
diff --git a/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/RowCustomKeyGenerator.java b/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/RowCustomKeyGenerator.java
index 125ae042..7ba218a7 100644
--- a/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/RowCustomKeyGenerator.java
+++ b/mybatis-flex-core/src/main/java/com/mybatisflex/core/keygen/RowCustomKeyGenerator.java
@@ -20,6 +20,7 @@ import com.mybatisflex.core.FlexConsts;
 import com.mybatisflex.core.exception.FlexExceptions;
 import com.mybatisflex.core.row.Row;
 import com.mybatisflex.core.row.RowKey;
+import com.mybatisflex.core.util.StringUtil;
 import org.apache.ibatis.executor.Executor;
 import org.apache.ibatis.executor.keygen.KeyGenerator;
 import org.apache.ibatis.mapping.MappedStatement;
@@ -58,11 +59,11 @@ public class RowCustomKeyGenerator implements KeyGenerator {
         try {
             Object existId = row.get(rowKey.getKeyColumn());
             // 若用户主动设置了主键，则使用用户自己设置的主键，不再生成主键
-            if (existId != null) {
-                return;
+            // 只有主键为 null 或者 空字符串时，对主键进行设置
+            if (existId == null || (existId instanceof String && StringUtil.isBlank((String) existId))) {
+                Object generateId = keyGenerator.generate(row, rowKey.getKeyColumn());
+                row.put(rowKey.getKeyColumn(), generateId);
             }
-            Object generateId = keyGenerator.generate(row, rowKey.getKeyColumn());
-            row.put(rowKey.getKeyColumn(), generateId);
         } catch (Exception e) {
             throw FlexExceptions.wrap(e);
         }