diff --git a/backend/src/services/risk.service.ts b/backend/src/services/risk.service.ts
index 1e8da3f..127e8b2 100644
--- a/backend/src/services/risk.service.ts
+++ b/backend/src/services/risk.service.ts
@@ -145,6 +145,16 @@ function calcPriority(
   return 'LOW'
 }
 
+/**
+ * 格式化时长：不足30天用"X天"，超过30天用"X个月Y天"
+ */
+function formatDuration(days: number): string {
+  if (days < 30) return `${days}天`
+  const months = Math.floor(days / 30)
+  const remainDays = days % 30
+  return remainDays === 0 ? `${months}个月` : `${months}个月${remainDays}天`
+}
+
 export async function detectContractRisks(orgId: string) {
   const today = new Date()
   today.setHours(0, 0, 0, 0)
@@ -165,7 +175,7 @@ export async function detectContractRisks(orgId: string) {
           employeeId: emp.id,
           type: 'CONTRACT',
           level: 'HIGH',
-          title: `${emp.name}入职${Math.round(days / 30)}个月未签合同，已视为无固定期限`,
+          title: `${emp.name}入职${formatDuration(days)}未签合同，已视为无固定期限`,
           description: `入职日期 ${emp.hireDate.toISOString().slice(0, 10)}，超过1年未签订书面合同，法律上已视为无固定期限劳动合同。`,
           actionUrl: `/roster?employee=${encodeURIComponent(emp.name)}`,
         })
@@ -174,7 +184,7 @@ export async function detectContractRisks(orgId: string) {
           employeeId: emp.id,
           type: 'CONTRACT',
           level: 'HIGH',
-          title: `${emp.name}入职${Math.round(days / 30)}个月未签合同`,
+          title: `${emp.name}入职${formatDuration(days)}未签合同`,
           description: `入职日期 ${emp.hireDate.toISOString().slice(0, 10)}，超过30天未签订书面合同，需尽快补签。`,
           actionUrl: `/roster?employee=${encodeURIComponent(emp.name)}`,
         })
@@ -183,7 +193,7 @@ export async function detectContractRisks(orgId: string) {
           employeeId: emp.id,
           type: 'CONTRACT',
           level: 'LOW',
-          title: `${emp.name}入职${Math.round(days / 30)}个月，尚未签合同`,
+          title: `${emp.name}入职${formatDuration(days)}，尚未签合同`,
           description: `入职日期 ${emp.hireDate.toISOString().slice(0, 10)}，30天内需签订书面合同。`,
           actionUrl: `/roster?employee=${encodeURIComponent(emp.name)}`,
         })
@@ -266,7 +276,7 @@ export async function detectOnboardingRisks(orgId: string) {
         employeeId: emp.id,
         type: 'ONBOARDING',
         level: daysSinceHire > 30 ? 'HIGH' : 'MEDIUM',
-        title: `${emp.name}入职手续未完成${daysSinceHire > 30 ? `（已超${Math.round(daysSinceHire / 30)}个月）` : ''}`,
+        title: `${emp.name}入职手续未完成${daysSinceHire > 30 ? `（已超${formatDuration(Math.round(daysSinceHire))}）` : ''}`,
         description: `入职日期 ${emp.hireDate.toISOString().slice(0, 10)}，尚未签订劳动合同，请尽快完成入职手续。`,
         actionUrl: `/roster?employee=${encodeURIComponent(emp.name)}`,
       })