diff --git a/src/controllers/SalaryRankEmployeeController.ts b/src/controllers/SalaryRankEmployeeController.ts
index ae5dacc..e09994b 100644
--- a/src/controllers/SalaryRankEmployeeController.ts
+++ b/src/controllers/SalaryRankEmployeeController.ts
@@ -14,6 +14,7 @@ import {
   Get,
   Query,
 } from "tsoa";
+import { Not } from "typeorm";
 import { AppDataSource } from "../database/data-source";
 import HttpSuccess from "../interfaces/http-success";
 import HttpStatusCode from "../interfaces/http-status";
@@ -54,6 +55,15 @@ export class SalaryRankEmployeeController extends Controller {
       if (!checkSalary) {
         throw new HttpError(HttpStatusCode.NOT_FOUND, "ไม่พบข้อมูลผังเงินเดือนนี้");
       }
+      const checkStep = await this.salaryRankEmployeeRepository.find({
+        where: { 
+          step: requestBody.step,
+          salaryEmployeeId: requestBody.salaryEmployeeId
+        }
+      });
+      if(checkStep.length > 0){
+        throw new HttpError(HttpStatusCode.NOT_FOUND, "ไม่สามารถเพิ่มได้ เนื่องจากลำดับขั้นนี้ซ้ำ");
+      }
       const salaryRankEmployee = Object.assign(new SalaryRankEmployee(), requestBody);
       salaryRankEmployee.createdUserId = request.user.sub;
       salaryRankEmployee.createdFullName = request.user.name;
@@ -85,6 +95,16 @@ export class SalaryRankEmployeeController extends Controller {
     if (!salaryRankEmployee) {
       throw new HttpError(HttpStatusCode.NOT_FOUND, "ไม่พบข้อมูลระดับผังเงินเดือนนี้");
     }
+    const checkStep = await this.salaryRankEmployeeRepository.find({
+      where: { 
+        id: Not(id),
+        step: requestBody.step,
+        salaryEmployeeId: salaryRankEmployee.salaryEmployeeId
+      }
+    });
+    if(checkStep.length > 0){
+      throw new HttpError(HttpStatusCode.NOT_FOUND, "ไม่สามารถแก้ไขได้ เนื่องจากลำดับขั้นนี้ซ้ำ");
+    }
     salaryRankEmployee.lastUpdateUserId = request.user.sub;
     salaryRankEmployee.lastUpdateFullName = request.user.name;
     this.salaryRankEmployeeRepository.merge(salaryRankEmployee, requestBody);