diff --git a/presentation/src/test/java/com/nexters/boolti/presentation/util/JwtUtilTest.kt b/presentation/src/test/java/com/nexters/boolti/presentation/util/JwtUtilTest.kt
index 72d7094c..3aa96714 100644
--- a/presentation/src/test/java/com/nexters/boolti/presentation/util/JwtUtilTest.kt
+++ b/presentation/src/test/java/com/nexters/boolti/presentation/util/JwtUtilTest.kt
@@ -1,5 +1,6 @@
 package com.nexters.boolti.presentation.util
 
+import io.kotest.assertions.throwables.shouldThrow
 import io.kotest.core.spec.style.BehaviorSpec
 import io.kotest.matchers.shouldBe
 
@@ -16,6 +17,24 @@ class JwtUtilTest : BehaviorSpec() {
                     payloadMap["sub"] shouldBe "3320565564"
                 }
             }
+
+            `when`("이 하이픈 들어간 jwt를 디코드 했을 때") {
+                then("payload의 key value 쌍을 반환한다.") {
+                    val payloadMap =
+                        sut.decodePayload("eyJraWQiOiI5ZjI1MmRhZGQ1ZjIzM2Y5M2QyZmE1MjhkMTJmZWEiLCJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.ewogICJhdWQiOiAiMmQ1Y2JlMGI0YmFjYzI1MzJmODcxNjZlMmE3ZTUzYjHvuqoiLAogICJzdWIiOiAiMzMyMDU2NTU2NCIsCiAgImF1dGhfdGltZSI6IDE3MDY2MTg0MTgsCiAgImlzcyI6ICJodHRwczovL2thdXRoLmtha2FvLmNvbSIsCiAgIm5pY2tuYW1lIjogIu2Zjeq4uOuPme-6kiIsCiAgImV4cCI6IDE3MDY2NjE2MTgsCiAgImlhdCI6IDE3MDY2MTg0MTgsCiAgInBpY3R1cmUiOiAiaHR0cDovL2sua2FrYW9jZG4ubmV0L2RuLzFHOWtwL2J0c0FvdDhsaU9uLzhDV3VkaTN1eTA3cnZGTlVrazNFUjAvaW1nXzExMHgxMTAuanBnIgp9.f-pvLKlSly9KCDBHc0d_-ccKlwr48ezCrLuwxiD5VCjLoEJRACCDnB49K3ygCTzLKZZHG5KNJNheVci5v7kdqegsxRa3xLcRLQ7Vz-NluSwFHiSe6Ska9QRXEDY1lOPRSh103b2fEEAykVUH6VqRwnal6S1-X3d9C3QMSvz1mXIUbqkFL5sCygbvszQY1cERC0NLQ55qIhD8AWTyeWKp_wQwvBpSW3WQEhjyWaTJZqrb9i7s5ZouqsK6B9rKmml3bM18qmLydh8ruV48yUbcI-Zm3ugwLI-8KZbfWASwCgEdyQYROq8fspziPdNXlSGnEnFRziwitP4ZFA5UVbt_FQ")
+                    payloadMap["nickname"] shouldBe "홍길동ﺒ"
+                    payloadMap["picture"] shouldBe "http://k.kakaocdn.net/dn/1G9kp/btsAot8liOn/8CWudi3uy07rvFNUkk3ER0/img_110x110.jpg"
+                    payloadMap["sub"] shouldBe "3320565564"
+                }
+            }
+
+            `when`("그런데 만약 JWT의 payload 부분이 표준대로 Base64 URL 인코드된 스트링이 아니라 그냥 Base64 인코딩된 스트링이라면") {
+                then("IllegalArgumentException을 터뜨린다.") {
+                    shouldThrow<IllegalArgumentException> {
+                        sut.decodePayload("eyJraWQiOiI5ZjI1MmRhZGQ1ZjIzM2Y5M2QyZmE1MjhkMTJmZWEiLCJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.ewogICJhdWQiOiAiMmQ1Y2JlMGI0YmFjYzI1MzJmODcxNjZlMmE3ZTUzYjHvuqoiLAogICJzdWIiOiAiMzMyMDU2NTU2NCIsCiAgImF1dGhfdGltZSI6IDE3MDY2MTg0MTgsCiAgImlzcyI6ICJodHRwczovL2thdXRoLmtha2FvLmNvbSIsCiAgIm5pY2tuYW1lIjogIu2Zjeq4uOuPme+6kiIsCiAgImV4cCI6IDE3MDY2NjE2MTgsCiAgImlhdCI6IDE3MDY2MTg0MTgsCiAgInBpY3R1cmUiOiAiaHR0cDovL2sua2FrYW9jZG4ubmV0L2RuLzFHOWtwL2J0c0FvdDhsaU9uLzhDV3VkaTN1eTA3cnZGTlVrazNFUjAvaW1nXzExMHgxMTAuanBnIgp9.f-pvLKlSly9KCDBHc0d_-ccKlwr48ezCrLuwxiD5VCjLoEJRACCDnB49K3ygCTzLKZZHG5KNJNheVci5v7kdqegsxRa3xLcRLQ7Vz-NluSwFHiSe6Ska9QRXEDY1lOPRSh103b2fEEAykVUH6VqRwnal6S1-X3d9C3QMSvz1mXIUbqkFL5sCygbvszQY1cERC0NLQ55qIhD8AWTyeWKp_wQwvBpSW3WQEhjyWaTJZqrb9i7s5ZouqsK6B9rKmml3bM18qmLydh8ruV48yUbcI-Zm3ugwLI-8KZbfWASwCgEdyQYROq8fspziPdNXlSGnEnFRziwitP4ZFA5UVbt_FQ")
+                    }
+                }
+            }
         }
     }
 }