diff --git a/be/src/olap/rowset/segment_v2/hierarchical_data_reader.cpp b/be/src/olap/rowset/segment_v2/hierarchical_data_reader.cpp
index c9516c870b8b9c..e739028a3e7b50 100644
--- a/be/src/olap/rowset/segment_v2/hierarchical_data_reader.cpp
+++ b/be/src/olap/rowset/segment_v2/hierarchical_data_reader.cpp
@@ -497,6 +497,11 @@ Status SparseColumnMergeReader::init(const ColumnIteratorOptions& opts) {
         const auto& path = entry->path.get_path();
         _sorted_src_subcolumn_for_sparse.emplace_back(StringRef(path.data(), path.size()), entry);
     }
+
+    // sort src subcolumns by path
+    std::sort(
+            _sorted_src_subcolumn_for_sparse.begin(), _sorted_src_subcolumn_for_sparse.end(),
+            [](const auto& lhsItem, const auto& rhsItem) { return lhsItem.first < rhsItem.first; });
     return Status::OK();
 }
 
@@ -536,11 +541,10 @@ void SparseColumnMergeReader::_process_data_without_sparse_column(vectorized::Mu
         auto& sparse_column_offsets = map_column.get_offsets();
         for (size_t i = 0; i != num_rows; ++i) {
             // Paths in sorted_src_subcolumn_for_sparse_column are already sorted.
-            for (const auto& entry : _src_subcolumns_for_sparse) {
-                const auto& path = entry->path.get_path();
-                _serialize_nullable_column_to_sparse(entry.get(), sparse_column_keys,
-                                                     sparse_column_values,
-                                                     StringRef(path.data(), path.size()), i);
+            for (const auto& entry : _sorted_src_subcolumn_for_sparse) {
+                const auto& path = entry.first;
+                _serialize_nullable_column_to_sparse(entry.second.get(), sparse_column_keys,
+                                                     sparse_column_values, path, i);
             }
             sparse_column_offsets.push_back(sparse_column_keys.size());
         }