diff --git a/em-oop/src/day3Keisho/Main.java b/em-oop/src/day3Keisho/Main.java
index 0edb324..20a3d02 100644
--- a/em-oop/src/day3Keisho/Main.java
+++ b/em-oop/src/day3Keisho/Main.java
@@ -1,5 +1,7 @@
 package day3Keisho;
 
+import java.util.Scanner;
+
 public class Main {
 
 	public static void main(String[] args) {
@@ -82,5 +84,43 @@ public class Main {
 		        System.out.println(emp.getMailAddress());
 		    }
 		}
+		// Stept 9
+		Scanner scanner = new Scanner(System.in);
+		System.out.print("検索したい部署名を入力してください: ");
+		String targetDepartmentName = scanner.nextLine();
+
+		String targetDepartmentId = null;
+
+		// ၁။ ဌာနနာမည်မှတစ်ဆင့် ဌာန ID (idDepartment) ကို ရှာခြင်း
+		for (BaseData data : allData) {
+		    if (data instanceof DepartmentData) {
+		        DepartmentData dept = (DepartmentData) data;
+		        if (targetDepartmentName.equals(dept.getNmDepartment())) {
+		            targetDepartmentId = dept.getIdDepartment();
+		            break;
+		        }
+		    }
+		}
+
+		// ၂။ ဌာန ID တူညီသည့် ဝန်ထမ်းများကို ရှာဖွေပြီး ထုတ်ပြခြင်း
+		if (targetDepartmentId != null) {
+		    boolean found = false;
+		    for (BaseData data : allData) {
+		        if (data instanceof EmployeeData) {
+		            EmployeeData emp = (EmployeeData) data;
+		            if (targetDepartmentId.equals(emp.getIdDepartment())) {
+		                System.out.println(emp.getNmEmployee() + "\t" + emp.getMailAddress());
+		                found = true;
+		            }
+		        }
+		    }
+		    if (!found) {
+		        System.out.println("その部署に所属する社員は見つかりませんでした");
+		    }
+		} else {
+		    System.out.println("該当する部署が見つかりませんでした");
+		}
+
+		scanner.close();
 	}
 }