diff --git a/tutorial.xcodeproj/project.xcworkspace/xcuserdata/raymondkim.xcuserdatad/UserInterfaceState.xcuserstate b/tutorial.xcodeproj/project.xcworkspace/xcuserdata/raymondkim.xcuserdatad/UserInterfaceState.xcuserstate
index 2a4b582..f68aa93 100644
Binary files a/tutorial.xcodeproj/project.xcworkspace/xcuserdata/raymondkim.xcuserdatad/UserInterfaceState.xcuserstate and b/tutorial.xcodeproj/project.xcworkspace/xcuserdata/raymondkim.xcuserdatad/UserInterfaceState.xcuserstate differ
diff --git a/tutorial/Views/Helpers/FavoriteButton.swift b/tutorial/Views/Helpers/FavoriteButton.swift
new file mode 100644
index 0000000..bc5eb55
--- /dev/null
+++ b/tutorial/Views/Helpers/FavoriteButton.swift
@@ -0,0 +1,34 @@
+//
+//  FavoriteButton.swift
+//  tutorial
+//
+//  Created by 김제필 on 8/11/22.
+//
+
+import SwiftUI
+
+struct FavoriteButton: View {
+    // 3.6.2. 버튼의 현재 상태를 저장할 변수 isSet을 선언하고 @Binding 프로퍼티 래퍼를 추가한다. ⬇️
+    @Binding var isSet: Bool
+
+    var body: some View {
+        // 3.6.3. 버튼 생성 -> 기본 형태 지정
+        Button {
+            isSet.toggle()
+        } label: {
+            Label("Toggle Favorite", systemImage: isSet ? "star.fill" : "star")
+                .labelStyle(.iconOnly)
+                .foregroundColor(isSet ? .yellow : .gray)
+        }
+    }
+}
+
+struct FavoriteButton_Previews: PreviewProvider {
+    static var previews: some View {
+        // 3.6.2. ⬆️ 변수 isSet을 프리뷰에 추가한다.
+        FavoriteButton(isSet: .constant(true))
+    }
+}
+
+
+// 3.6.3. 까지 도달했으면 LandmarkDetail.swift 파일로 이동
diff --git a/tutorial/Views/Landmarks/LandmarkDetail.swift b/tutorial/Views/Landmarks/LandmarkDetail.swift
index ea1c206..a945cac 100644
--- a/tutorial/Views/Landmarks/LandmarkDetail.swift
+++ b/tutorial/Views/Landmarks/LandmarkDetail.swift
@@ -10,6 +10,13 @@
 import SwiftUI
 
 struct LandmarkDetail: View {
+    // 3.6.5. computed property landmarkIndex를 생성하여 EnvironmentalObjet 변수인 modelData와 비교한다.
+    @EnvironmentObject var modelData: ModelData
+
+    var landmarkIndex: Int {
+        modelData.landmarks.firstIndex(where: { $0.id == landmark.id})!
+    }
+
     // 2.7.6. Landmark 프로퍼티 추가. 프리뷰 코드로 이동 ⬇️
     var landmark: Landmark
 
@@ -32,8 +39,13 @@ struct LandmarkDetail: View {
 
             // 1.3.1., 1.3.2. VStack 추가
             VStack(alignment: .leading) {  // 1.3.5. alignment 옵션 추가
-                Text(landmark.name)  // 2.7.8. 필요한 데이터 추가
-                    .font(.title)
+                // 3.6.6. HStack 내로 landmark.name TextView를 이동하고 옆에 FavoriteButton 추가
+                HStack {
+                    Text(landmark.name)  // 2.7.8. 필요한 데이터 추가
+                        .font(.title)
+
+                    FavoriteButton(isSet: $modelData.landmarks[landmarkIndex].isFavorite)
+                }
 
                 // 1.3.6. HStack 추가
                 HStack {