diff --git a/server/api/salary.go b/server/api/salary.go
index 7505dea..def52f5 100644
--- a/server/api/salary.go
+++ b/server/api/salary.go
@@ -27,7 +27,7 @@ type Salary struct {
 	OtherDeduct    string `json:"other_deduct,omitempty"`
 	CreateTime     string `json:"create_time,omitempty"`
 	UpdateTime     string `json:"update_time,omitempty"`
-	Extra          string `json:"extra"`
+	Extra          string `json:"extra,omitempty"`
 }
 
 type CreateSalaryReq struct {