diff --git a/be/src/olap/rowset/segment_v2/variant/variant_column_reader.cpp b/be/src/olap/rowset/segment_v2/variant/variant_column_reader.cpp
index ec0079edc64635..be28a27272be75 100644
--- a/be/src/olap/rowset/segment_v2/variant/variant_column_reader.cpp
+++ b/be/src/olap/rowset/segment_v2/variant/variant_column_reader.cpp
@@ -225,6 +225,11 @@ Status VariantColumnReader::_new_iterator_with_flat_leaves(ColumnIteratorUPtr* i
             target_col.has_path_info() ? _subcolumns_meta_info->find_leaf(relative_path) : nullptr;
     if (!node) {
         if (relative_path.get_path() == SPARSE_COLUMN_PATH) {
+            if (_sparse_column_reader == nullptr) {
+                return Status::InternalError(
+                        "Sparse column reader is not initialize, variant column is: {}",
+                        target_col.path_info_ptr()->get_path());
+            }
             // read sparse column and filter extracted columns in subcolumn_path_map
             std::unique_ptr<ColumnIterator> inner_iter;
             RETURN_IF_ERROR(_sparse_column_reader->new_iterator(&inner_iter, nullptr));
diff --git a/be/test/olap/rowset/segment_v2/variant_column_writer_reader_test.cpp b/be/test/olap/rowset/segment_v2/variant_column_writer_reader_test.cpp
index 8495e7c4e0bdc6..cdef8725dacea7 100644
--- a/be/test/olap/rowset/segment_v2/variant_column_writer_reader_test.cpp
+++ b/be/test/olap/rowset/segment_v2/variant_column_writer_reader_test.cpp
@@ -715,6 +715,14 @@ TEST_F(VariantColumnWriterReaderTest, test_write_data_normal) {
     EXPECT_TRUE(st.ok()) << st.msg();
     EXPECT_TRUE(assert_cast<DefaultValueColumnIterator*>(it7.get()) != nullptr);
     EXPECT_TRUE(io::global_local_filesystem()->delete_directory(_tablet->tablet_path()).ok());
+
+    // 20. check sparse column reader is nullptr
+    ColumnIteratorUPtr it_error;
+    variant_column_reader->_sparse_column_reader = nullptr;
+    st = variant_column_reader->new_iterator(&it_error, &sparse_column, &storage_read_opts,
+                                             &column_reader_cache);
+    EXPECT_FALSE(st.ok()) << st.msg();
+    EXPECT_TRUE(it_error == nullptr);
 }
 
 TEST_F(VariantColumnWriterReaderTest, test_write_data_advanced) {