diff --git a/domain/src/main/kotlin/com/threedays/domain/auth/entity/AuthCode.kt b/domain/src/main/kotlin/com/threedays/domain/auth/entity/AuthCode.kt
new file mode 100644
index 0000000..24e4d20
--- /dev/null
+++ b/domain/src/main/kotlin/com/threedays/domain/auth/entity/AuthCode.kt
@@ -0,0 +1,52 @@
+package com.threedays.domain.auth.entity
+
+import com.threedays.domain.auth.exception.AuthException
+import com.threedays.domain.auth.vo.AuthCodeId
+import com.threedays.support.common.base.domain.AggregateRoot
+import com.threedays.support.common.base.domain.UUIDTypeId
+import java.time.LocalDateTime
+
+data class AuthCode(
+    override val id: AuthCodeId,
+    val code: Code,
+    val expireAt: LocalDateTime,
+) : AggregateRoot<AuthCode, AuthCodeId>() {
+
+    @JvmInline
+    value class Code(val value: String) {
+
+        init {
+            require(value.length == 6) { "인증 코드는 6자리 숫자로 구성되어야 합니다." }
+            require(value.all { it.isDigit() }) { "인증 코드는 숫자로만 구성되어야 합니다." }
+        }
+
+        companion object {
+
+            fun generate(): Code {
+                val random: Int = (0..999999).random()
+                val code: String = random.toString().padStart(6, '0')
+                return Code(code)
+            }
+
+        }
+    }
+
+    companion object {
+
+        fun create(expireAt: LocalDateTime): AuthCode {
+            return AuthCode(UUIDTypeId.random(), Code.generate(), expireAt)
+        }
+
+    }
+
+    fun verify(code: Code) {
+        if (this.code != code) {
+            throw AuthException.InvalidAuthCodeException()
+        }
+
+        if (LocalDateTime.now() > expireAt) {
+            throw AuthException.AuthCodeExpiredException()
+        }
+    }
+
+}
diff --git a/domain/src/main/kotlin/com/threedays/domain/auth/exception/AuthException.kt b/domain/src/main/kotlin/com/threedays/domain/auth/exception/AuthException.kt
new file mode 100644
index 0000000..a3b0b59
--- /dev/null
+++ b/domain/src/main/kotlin/com/threedays/domain/auth/exception/AuthException.kt
@@ -0,0 +1,18 @@
+package com.threedays.domain.auth.exception
+
+import com.threedays.support.common.base.exception.CustomException
+
+sealed class AuthException(
+    codeNumber: Int,
+    override val message: String = DEFAULT_MESSAGE,
+) : CustomException("Auth", codeNumber, message) {
+
+    data class AuthCodeExpiredException(
+        override val message: String = "인증 코드가 만료되었습니다.",
+    ) : AuthException(1001, message)
+
+    data class InvalidAuthCodeException(
+        override val message: String = "유효하지 않은 인증 코드입니다.",
+    ) : AuthException(1002, message)
+
+}
diff --git a/domain/src/main/kotlin/com/threedays/domain/auth/repository/AuthCodeRepository.kt b/domain/src/main/kotlin/com/threedays/domain/auth/repository/AuthCodeRepository.kt
new file mode 100644
index 0000000..8f0a9fa
--- /dev/null
+++ b/domain/src/main/kotlin/com/threedays/domain/auth/repository/AuthCodeRepository.kt
@@ -0,0 +1,7 @@
+package com.threedays.domain.auth.repository
+
+import com.threedays.domain.auth.entity.AuthCode
+import com.threedays.domain.auth.vo.AuthCodeId
+import com.threedays.support.common.base.domain.Repository
+
+interface AuthCodeRepository : Repository<AuthCode, AuthCodeId>
diff --git a/domain/src/main/kotlin/com/threedays/domain/auth/vo/AuthCodeId.kt b/domain/src/main/kotlin/com/threedays/domain/auth/vo/AuthCodeId.kt
new file mode 100644
index 0000000..dd0806d
--- /dev/null
+++ b/domain/src/main/kotlin/com/threedays/domain/auth/vo/AuthCodeId.kt
@@ -0,0 +1,6 @@
+package com.threedays.domain.auth.vo
+
+import com.threedays.support.common.base.domain.UUIDTypeId
+import java.util.*
+
+data class AuthCodeId(override val value: UUID) : UUIDTypeId(value)
diff --git a/domain/src/test/kotlin/com/threedays/domain/auth/entity/AuthCodeTest.kt b/domain/src/test/kotlin/com/threedays/domain/auth/entity/AuthCodeTest.kt
new file mode 100644
index 0000000..3c79a02
--- /dev/null
+++ b/domain/src/test/kotlin/com/threedays/domain/auth/entity/AuthCodeTest.kt
@@ -0,0 +1,117 @@
+package com.threedays.domain.auth.entity
+
+import com.threedays.domain.auth.exception.AuthException
+import io.kotest.assertions.throwables.shouldNotThrow
+import io.kotest.assertions.throwables.shouldThrow
+import io.kotest.core.annotation.DisplayName
+import io.kotest.core.spec.style.DescribeSpec
+import io.kotest.matchers.shouldBe
+import io.kotest.matchers.shouldNotBe
+import java.time.LocalDateTime
+
+@DisplayName("[도메인] - 인증 코드")
+class AuthCodeTest : DescribeSpec({
+
+    describe("인증 코드 생성") {
+        it("새로운 인증 코드를 생성한다") {
+            // arrange
+            val expireAt = LocalDateTime.now().plusMinutes(5)
+
+            // act
+            val authCode = AuthCode.create(expireAt)
+
+            // assert
+            authCode.id shouldNotBe null
+            authCode.code.value.length shouldBe 6
+            authCode.code.value.all { it.isDigit() } shouldBe true
+            authCode.expireAt shouldBe expireAt
+        }
+    }
+
+    describe("인증 코드 검증") {
+        context("유효한 인증 코드로") {
+            it("검증에 성공한다") {
+                // arrange
+                val expireAt: LocalDateTime = LocalDateTime.now().plusMinutes(5)
+                val authCode = AuthCode.create(expireAt)
+                val validCode = authCode.code
+
+                // act & assert
+                shouldNotThrow<AuthException> {
+                    authCode.verify(validCode)
+                }
+            }
+        }
+
+        context("잘못된 인증 코드로") {
+            it("InvalidAuthCodeException을 발생시킨다") {
+                // arrange
+                val expireAt = LocalDateTime.now().plusMinutes(5)
+                val authCode = AuthCode.create(expireAt)
+                val invalidCode = AuthCode.Code("000000")
+
+                // act & assert
+                shouldThrow<AuthException.InvalidAuthCodeException> {
+                    authCode.verify(invalidCode)
+                }
+            }
+        }
+
+        context("만료된 인증 코드로") {
+            it("AuthCodeExpiredException을 발생시킨다") {
+                // arrange
+                val expireAt = LocalDateTime.now().minusMinutes(1)
+                val authCode = AuthCode.create(expireAt)
+
+                // act & assert
+                shouldThrow<AuthException.AuthCodeExpiredException> {
+                    authCode.verify(authCode.code)
+                }
+            }
+        }
+    }
+
+    describe("인증 코드 값 객체 (Code)") {
+        context("유효한 코드로") {
+            it("Code 객체를 생성한다") {
+                // act
+                val code = AuthCode.Code("123456")
+
+                // assert
+                code.value shouldBe "123456"
+            }
+        }
+
+        context("6자리가 아닌 코드로") {
+            it("예외를 발생시킨다") {
+                // act & assert
+                shouldThrow<IllegalArgumentException> {
+                    AuthCode.Code("12345")
+                }
+                shouldThrow<IllegalArgumentException> {
+                    AuthCode.Code("1234567")
+                }
+            }
+        }
+
+        context("숫자가 아닌 문자가 포함된 코드로") {
+            it("예외를 발생시킨다") {
+                // act & assert
+                shouldThrow<IllegalArgumentException> {
+                    AuthCode.Code("12345a")
+                }
+            }
+        }
+
+        context("코드 생성 시") {
+            it("6자리 숫자로 구성된 코드를 생성한다") {
+                // act
+                val generatedCode = AuthCode.Code.generate()
+
+                // assert
+                generatedCode.value.length shouldBe 6
+                generatedCode.value.all { it.isDigit() } shouldBe true
+            }
+        }
+    }
+})
diff --git a/openapi b/openapi
index 7f7f28b..9c4762a 160000
--- a/openapi
+++ b/openapi
@@ -1 +1 @@
-Subproject commit 7f7f28bcfc288b15b46a9c8d5b1545b4340f3e29
+Subproject commit 9c4762a9b91518c80ee3a5282b097a572aea3176