diff --git a/modules/indexer/issues/bleve/bleve.go b/modules/indexer/issues/bleve/bleve.go
index f7dd6ea03d5..af9305b1ba2 100644
--- a/modules/indexer/issues/bleve/bleve.go
+++ b/modules/indexer/issues/bleve/bleve.go
@@ -83,7 +83,7 @@ func generateIssueIndexMapping() (mapping.IndexMapping, error) {
 	docMapping.AddFieldMappingsAt("label_ids", numberFieldMapping)
 	docMapping.AddFieldMappingsAt("no_label", boolFieldMapping)
 	docMapping.AddFieldMappingsAt("milestone_id", numberFieldMapping)
-	docMapping.AddFieldMappingsAt("project_id", numberFieldMapping)
+	docMapping.AddFieldMappingsAt("project_ids", numberFieldMapping)
 	docMapping.AddFieldMappingsAt("project_board_id", numberFieldMapping)
 	docMapping.AddFieldMappingsAt("poster_id", numberFieldMapping)
 	docMapping.AddFieldMappingsAt("assignee_id", numberFieldMapping)
diff --git a/modules/indexer/issues/elasticsearch/elasticsearch.go b/modules/indexer/issues/elasticsearch/elasticsearch.go
index 1bcbd67c1d1..bb89994b2c8 100644
--- a/modules/indexer/issues/elasticsearch/elasticsearch.go
+++ b/modules/indexer/issues/elasticsearch/elasticsearch.go
@@ -68,7 +68,7 @@ const (
 			"label_ids": { "type": "integer", "index": true },
 			"no_label": { "type": "boolean", "index": true },
 			"milestone_id": { "type": "integer", "index": true },
-			"project_id": { "type": "integer", "index": true },
+			"project_ids": { "type": "integer", "index": true },
 			"project_board_id": { "type": "integer", "index": true },
 			"poster_id": { "type": "integer", "index": true },
 			"assignee_id": { "type": "integer", "index": true },
@@ -205,7 +205,7 @@ func (b *Indexer) Search(ctx context.Context, options *internal.SearchOptions) (
 	}
 
 	if len(options.ProjectIDs) > 0 {
-		query.Must(elastic.NewTermsQuery("project_id", toAnySlice(options.ProjectIDs)...))
+		query.Must(elastic.NewTermsQuery("project_ids", toAnySlice(options.ProjectIDs)...))
 	}
 	if options.ProjectColumnID.Has() {
 		query.Must(elastic.NewTermQuery("project_board_id", options.ProjectColumnID.Value()))
diff --git a/modules/indexer/issues/internal/model.go b/modules/indexer/issues/internal/model.go
index 8a251dd2abc..f99df6c495c 100644
--- a/modules/indexer/issues/internal/model.go
+++ b/modules/indexer/issues/internal/model.go
@@ -30,7 +30,7 @@ type IndexerData struct {
 	LabelIDs           []int64            `json:"label_ids"`
 	NoLabel            bool               `json:"no_label"` // True if LabelIDs is empty
 	MilestoneID        int64              `json:"milestone_id"`
-	ProjectIDs         []int64            `json:"project_id"`
+	ProjectIDs         []int64            `json:"project_ids"`
 	ProjectColumnID    int64              `json:"project_board_id"` // the key should be kept as project_board_id to keep compatible
 	PosterID           int64              `json:"poster_id"`
 	AssigneeID         int64              `json:"assignee_id"`
diff --git a/modules/indexer/issues/meilisearch/meilisearch.go b/modules/indexer/issues/meilisearch/meilisearch.go
index c1edcfbe38b..c5bb7186913 100644
--- a/modules/indexer/issues/meilisearch/meilisearch.go
+++ b/modules/indexer/issues/meilisearch/meilisearch.go
@@ -70,7 +70,7 @@ func NewIndexer(url, apiKey, indexerName string) *Indexer {
 			"label_ids",
 			"no_label",
 			"milestone_id",
-			"project_id",
+			"project_ids",
 			"project_board_id",
 			"poster_id",
 			"assignee_id",