diff --git a/kotlin-basic/src/main/kotlin/11_Interface.kt b/kotlin-basic/src/main/kotlin/11_Interface.kt
new file mode 100644
index 00000000..483f2a8a
--- /dev/null
+++ b/kotlin-basic/src/main/kotlin/11_Interface.kt
@@ -0,0 +1,52 @@
+class Product(val name: String, val price: Int)
+
+interface Wheel {
+    fun roll()
+}
+
+interface Cart: Wheel {
+
+    val coin: Int
+
+    val weight: String
+        get() = "20kg" // backing field 사용 불가
+
+    fun add(product: Product)
+
+    fun rent() {
+        if (coin > 0) {
+            println("카트를 대여합니다.")
+        }
+    }
+
+    override fun roll() {
+        println("카트가 굴러갑니다.")
+    }
+
+}
+
+interface Order {
+
+    fun add(product: Product) {
+        println("${product.name} 주문이 완료되었습니다.")
+    }
+}
+
+class MyCart(override val coin: Int) : Cart, Order {
+
+    override fun add(product: Product) {
+        if (coin <= 0) println("코인을 넣어주세요.")
+        else println("${product.name}이(가) 카트에 추가됐습니다.")
+
+        // 다중 상속
+        super<Order>.add(product)
+    }
+}
+
+
+fun main() {
+    val cart = MyCart(coin = 100)
+    cart.rent()
+    cart.roll()
+    cart.add(Product(name = "장난감", price = 1000))
+}
\ No newline at end of file