diff --git a/internal/util/indexparams/disk_index_params.go b/internal/util/indexparams/disk_index_params.go
index 0f67d83c13..8b8298d2c7 100644
--- a/internal/util/indexparams/disk_index_params.go
+++ b/internal/util/indexparams/disk_index_params.go
@@ -17,7 +17,6 @@
 package indexparams
 
 import (
-	"encoding/json"
 	"fmt"
 	"strconv"
 	"unsafe"
@@ -76,8 +75,10 @@ func FillDiskIndexParams(params *paramtable.ComponentParam, indexParams map[stri
 		if !ok {
 			return fmt.Errorf("index param search_list_size not exist")
 		}
-		extraParams := autoindex.BigDataIndexExtraParams{}
-		json.Unmarshal([]byte(params.AutoIndexConfig.ExtraParams.GetValue()), &extraParams)
+		extraParams, err := autoindex.NewBigDataExtraParamsFromJSON(params.AutoIndexConfig.ExtraParams.GetValue())
+		if err != nil {
+			return err
+		}
 		pqCodeBudgetGBRatio = fmt.Sprintf("%f", extraParams.PQCodeBudgetGBRatio)
 		buildNumThreadsRatio = fmt.Sprintf("%f", extraParams.BuildNumThreadsRatio)
 		searchCacheBudgetGBRatio = fmt.Sprintf("%f", extraParams.SearchCacheBudgetGBRatio)
diff --git a/internal/util/indexparams/disk_index_params_test.go b/internal/util/indexparams/disk_index_params_test.go
index 2353ebe7a0..2eaf60103a 100644
--- a/internal/util/indexparams/disk_index_params_test.go
+++ b/internal/util/indexparams/disk_index_params_test.go
@@ -65,9 +65,8 @@ func TestDiskIndexParams(t *testing.T) {
 		mapString := make(map[string]string)
 		mapString[autoindex.BuildRatioKey] = "{\"pq_code_budget_gb\": 0.125, \"num_threads\": 1}"
 		mapString[autoindex.PrepareRatioKey] = "{\"search_cache_budget_gb\": 0.225, \"num_threads\": 4}"
-		extraParams, err := autoindex.NewBigDataExtraParamsFromMap(mapString)
-		assert.NoError(t, err)
-		str, err := json.Marshal(extraParams)
+
+		str, err := json.Marshal(mapString)
 		assert.NoError(t, err)
 		params.Save(params.AutoIndexConfig.ExtraParams.Key, string(str))
 		indexParams := make(map[string]string)
@@ -103,6 +102,46 @@ func TestDiskIndexParams(t *testing.T) {
 		assert.Equal(t, 4.0, beamWidthRatio)
 	})
 
+	t.Run("fill index params with wrong auto index param", func(t *testing.T) {
+		var params paramtable.ComponentParam
+		params.Init()
+		params.Save(params.AutoIndexConfig.Enable.Key, "true")
+		// ExtraParams wrong
+		params.Save(params.AutoIndexConfig.ExtraParams.Key, "")
+		indexParams := make(map[string]string)
+		indexParams["max_degree"] = "56"
+		indexParams["search_list_size"] = "100"
+		indexParams["index_type"] = "DISKANN"
+		str, err := json.Marshal(indexParams)
+		assert.NoError(t, err)
+		params.Save(params.AutoIndexConfig.IndexParams.Key, string(str))
+
+		indexParams = make(map[string]string)
+		err = FillDiskIndexParams(&params, indexParams)
+		assert.Error(t, err)
+
+		// IndexParams wrong
+		mapString := make(map[string]string)
+		mapString[autoindex.BuildRatioKey] = "{\"pq_code_budget_gb\": 0.125, \"num_threads\": 1}"
+		mapString[autoindex.PrepareRatioKey] = "{\"search_cache_budget_gb\": 0.225, \"num_threads\": 4}"
+
+		str, err = json.Marshal(mapString)
+		assert.NoError(t, err)
+		params.Save(params.AutoIndexConfig.ExtraParams.Key, string(str))
+
+		indexParams = make(map[string]string)
+		indexParams["max_degree"] = "56"
+		indexParams["search_list"] = "100" // should be search_list_size
+		indexParams["index_type"] = "DISKANN"
+		str, err = json.Marshal(indexParams)
+		assert.NoError(t, err)
+		params.Save(params.AutoIndexConfig.IndexParams.Key, string(str))
+
+		indexParams = make(map[string]string)
+		err = FillDiskIndexParams(&params, indexParams)
+		assert.Error(t, err)
+	})
+
 	t.Run("set disk index build params", func(t *testing.T) {
 		indexParams := make(map[string]string)
 		indexParams[PQCodeBudgetRatioKey] = "0.125"