diff --git a/internal/httpapi/attendance_payload_test.go b/internal/httpapi/attendance_payload_test.go
new file mode 100644
index 0000000..efdf720
--- /dev/null
+++ b/internal/httpapi/attendance_payload_test.go
@@ -0,0 +1,40 @@
+package httpapi
+
+import (
+	"testing"
+	"time"
+
+	"git.118im.com/im_team/im_workbench/internal/store"
+)
+
+func TestAttendanceCheckinPayloadReturnsJSONObjectFields(t *testing.T) {
+	now := time.Date(2026, 9, 18, 1, 27, 49, 0, time.UTC)
+	payload := attendanceCheckinPayload(store.AttendanceCheckin{
+		CheckinID:  "attc_1",
+		Action:     "check_in",
+		ClientTime: now,
+		ServerTime: now,
+		Result:     "normal",
+		Location:   `{"name":"当前位置","latitude":22.929670335639365}`,
+		Wifi:       `{}`,
+		Device:     `{"platform":"ios","device_id":"C7A76C6A-FC57-4CED-B1C1-CE5199944F8C"}`,
+	})
+
+	location, ok := payload["location"].(map[string]any)
+	if !ok {
+		t.Fatalf("location=%T, want map[string]any", payload["location"])
+	}
+	if location["name"] != "当前位置" {
+		t.Fatalf("location=%v", location)
+	}
+	if _, ok := payload["wifi"].(map[string]any); !ok {
+		t.Fatalf("wifi=%T, want map[string]any", payload["wifi"])
+	}
+	device, ok := payload["device"].(map[string]any)
+	if !ok {
+		t.Fatalf("device=%T, want map[string]any", payload["device"])
+	}
+	if device["platform"] != "ios" {
+		t.Fatalf("device=%v", device)
+	}
+}
diff --git a/internal/httpapi/payload.go b/internal/httpapi/payload.go
index 70ef3f7..151c488 100644
--- a/internal/httpapi/payload.go
+++ b/internal/httpapi/payload.go
@@ -164,9 +164,9 @@ func attendanceCheckinPayload(checkin store.AttendanceCheckin) map[string]any {
 		"client_time": checkin.ClientTime.UTC().Format(time.RFC3339Nano),
 		"server_time": checkin.ServerTime.UTC().Format(time.RFC3339Nano),
 		"result":      checkin.Result,
-		"location":    checkin.Location,
-		"wifi":        checkin.Wifi,
-		"device":      checkin.Device,
+		"location":    jsonObject(checkin.Location),
+		"wifi":        jsonObject(checkin.Wifi),
+		"device":      jsonObject(checkin.Device),
 	}
 }