diff --git a/configs/milvus.yaml b/configs/milvus.yaml
index fa43ae0963..4e2be888f8 100644
--- a/configs/milvus.yaml
+++ b/configs/milvus.yaml
@@ -735,6 +735,7 @@ dataCoord:
     mixCompactionUsage: 4 # slot usage of mix compaction task.
     l0DeleteCompactionUsage: 8 # slot usage of l0 compaction task.
     indexTaskSlotUsage: 64 # slot usage of index task per 512mb
+    scalarIndexTaskSlotUsage: 16 # slot usage of scalar index task per 512mb
     statsTaskSlotUsage: 8 # slot usage of stats task per 512mb
     analyzeTaskSlotUsage: 65535 # slot usage of analyze task
   jsonShreddingTriggerCount: 10 # jsonkey stats task count per trigger
diff --git a/internal/datacoord/index_inspector.go b/internal/datacoord/index_inspector.go
index 889b0adae1..a619489d20 100644
--- a/internal/datacoord/index_inspector.go
+++ b/internal/datacoord/index_inspector.go
@@ -175,13 +175,14 @@ func (i *indexInspector) createIndexForSegment(ctx context.Context, segment *Seg
 	if err != nil {
 		return err
 	}
-	taskSlot := calculateIndexTaskSlot(segment.getSegmentSize())
 
 	indexParams := i.meta.indexMeta.GetIndexParams(segment.CollectionID, indexID)
 	indexType := GetIndexType(indexParams)
+	isVectorIndex := vecindexmgr.GetVecIndexMgrInstance().IsVecIndex(indexType)
+	taskSlot := calculateIndexTaskSlot(segment.getSegmentSize(), isVectorIndex)
 
 	// rewrite the index type if needed, and this final index type will be persisted in the meta
-	if vecindexmgr.GetVecIndexMgrInstance().IsVecIndex(indexType) && Params.KnowhereConfig.Enable.GetAsBool() {
+	if isVectorIndex && Params.KnowhereConfig.Enable.GetAsBool() {
 		var err error
 		indexParams, err = Params.KnowhereConfig.UpdateIndexParams(indexType, paramtable.BuildStage, indexParams)
 		if err != nil {
@@ -227,9 +228,14 @@ func (i *indexInspector) reloadFromMeta() {
 				continue
 			}
 
+			indexParams := i.meta.indexMeta.GetIndexParams(segment.CollectionID, segIndex.IndexID)
+			indexType := GetIndexType(indexParams)
+			isVectorIndex := vecindexmgr.GetVecIndexMgrInstance().IsVecIndex(indexType)
+			taskSlot := calculateIndexTaskSlot(segment.getSegmentSize(), isVectorIndex)
+
 			i.scheduler.Enqueue(newIndexBuildTask(
 				model.CloneSegmentIndex(segIndex),
-				calculateIndexTaskSlot(segment.getSegmentSize()),
+				taskSlot,
 				i.meta,
 				i.handler,
 				i.storageCli,
diff --git a/internal/datacoord/util.go b/internal/datacoord/util.go
index be0024142f..f9f359c6b9 100644
--- a/internal/datacoord/util.go
+++ b/internal/datacoord/util.go
@@ -369,8 +369,11 @@ func getSortStatus(sorted bool) string {
 	return "unsorted"
 }
 
-func calculateIndexTaskSlot(segmentSize int64) int64 {
+func calculateIndexTaskSlot(segmentSize int64, isVectorIndex bool) int64 {
 	defaultSlots := Params.DataCoordCfg.IndexTaskSlotUsage.GetAsInt64()
+	if !isVectorIndex {
+		defaultSlots = Params.DataCoordCfg.ScalarIndexTaskSlotUsage.GetAsInt64()
+	}
 	if segmentSize > 512*1024*1024 {
 		taskSlot := max(segmentSize/512/1024/1024, 1) * defaultSlots
 		return max(taskSlot, 1)
diff --git a/pkg/util/paramtable/component_param.go b/pkg/util/paramtable/component_param.go
index 073f9e6533..f95c83803d 100644
--- a/pkg/util/paramtable/component_param.go
+++ b/pkg/util/paramtable/component_param.go
@@ -4617,6 +4617,7 @@ type dataCoordConfig struct {
 	MixCompactionSlotUsage        ParamItem `refreshable:"true"`
 	L0DeleteCompactionSlotUsage   ParamItem `refreshable:"true"`
 	IndexTaskSlotUsage            ParamItem `refreshable:"true"`
+	ScalarIndexTaskSlotUsage      ParamItem `refreshable:"true"`
 	StatsTaskSlotUsage            ParamItem `refreshable:"true"`
 	AnalyzeTaskSlotUsage          ParamItem `refreshable:"true"`
 
@@ -5634,6 +5635,16 @@ if param targetVecIndexVersion is not set, the default value is -1, which means
 	}
 	p.IndexTaskSlotUsage.Init(base.mgr)
 
+	p.ScalarIndexTaskSlotUsage = ParamItem{
+		Key:          "dataCoord.slot.scalarIndexTaskSlotUsage",
+		Version:      "2.6.8",
+		Doc:          "slot usage of scalar index task per 512mb",
+		DefaultValue: "16",
+		PanicIfEmpty: false,
+		Export:       true,
+	}
+	p.ScalarIndexTaskSlotUsage.Init(base.mgr)
+
 	p.StatsTaskSlotUsage = ParamItem{
 		Key:          "dataCoord.slot.statsTaskSlotUsage",
 		Version:      "2.5.8",