diff --git a/src/main/java/com/yunhai/bschclassmanage/service/impl/classes/SchClassImportService.java b/src/main/java/com/yunhai/bschclassmanage/service/impl/classes/SchClassImportService.java
index d0f3d32..b707851 100644
--- a/src/main/java/com/yunhai/bschclassmanage/service/impl/classes/SchClassImportService.java
+++ b/src/main/java/com/yunhai/bschclassmanage/service/impl/classes/SchClassImportService.java
@@ -300,9 +300,7 @@ public class SchClassImportService {
         Integer stuParentId = stuGroup.getId();
 
         Map<Integer, List<SelectIntVO>> schGradeGroupMap = comSchTreeService.getSchGroupTypeList(schId, NodeType.GRADE.getId());
-        if (schGradeGroupMap.isEmpty()) {
-            throw new DException("该学制下没有学级，请先同步年级组数据！");
-        }
+
         // 构建「年级组ID -> (班级组名 -> 班级组ID)」映射，使同名班级按年级区分，避免跨年级误复用平台组
         Map<Integer, Map<String, Integer>> gradeClassGroupMap = buildGradeClassGroupMap(schId);
 
diff --git a/src/main/java/com/yunhai/bschclassmanage/service/impl/com/SendUserBaseService.java b/src/main/java/com/yunhai/bschclassmanage/service/impl/com/SendUserBaseService.java
index 8dfc7d9..5a076e3 100644
--- a/src/main/java/com/yunhai/bschclassmanage/service/impl/com/SendUserBaseService.java
+++ b/src/main/java/com/yunhai/bschclassmanage/service/impl/com/SendUserBaseService.java
@@ -23,6 +23,7 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 
 import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -236,7 +237,11 @@ public class SendUserBaseService implements ISendUserBaseService {
         if (groupIds == null) {
             return;
         }
-        for (Integer groupId : groupIds) {
+        // 从大到小排序后删除：子节点（班级组）的 groupId 通常大于父节点（年级组/学段组），
+        // 先删子节点再删父节点，避免平台树因父节点先删而报"存在子节点"等约束异常
+        List<Integer> sortedIds = new ArrayList<>(groupIds);
+        sortedIds.sort(Comparator.reverseOrder());
+        for (Integer groupId : sortedIds) {
             try {
                 deleteGroup(groupId, schId);
             } catch (Exception ignore) {