diff --git a/functions/api/routes/notice/active/activeGET.js b/functions/api/routes/notice/active/activeGET.js
index c96af63..b7adffa 100644
--- a/functions/api/routes/notice/active/activeGET.js
+++ b/functions/api/routes/notice/active/activeGET.js
@@ -6,6 +6,7 @@ const responseMessage = require('../../../../constants/responseMessage');
 const db = require('../../../../db/db');
 const slackAPI = require('../../../../middlewares/slackAPI');
 const { noticeDB } = require('../../../../db');
+const { passedDayToStr } = require('../../../../lib/passedDayToStr');
 
 /**
  *  @활동_알림_조회
@@ -45,7 +46,7 @@ module.exports = async (req, res) => {
       notice['noticeContent'] = a.content;
       notice['noticeImg'] = a.thumbnail;
       notice['isThumbProfile'] = a.isThumbProfile;
-      notice['day'] = passedDay > 0 ? `${passedDay}일전` : `오늘`;
+      notice['day'] = passedDayToStr(passedDay);
       notice['isNew'] = !a.isRead;
       return notice;
     });
diff --git a/functions/api/routes/notice/service/serviceGET.js b/functions/api/routes/notice/service/serviceGET.js
index 531816e..992b0af 100644
--- a/functions/api/routes/notice/service/serviceGET.js
+++ b/functions/api/routes/notice/service/serviceGET.js
@@ -6,6 +6,7 @@ const responseMessage = require('../../../../constants/responseMessage');
 const db = require('../../../../db/db');
 const slackAPI = require('../../../../middlewares/slackAPI');
 const { noticeDB } = require('../../../../db');
+const { passedDayToStr } = require('../../../../lib/passedDayToStr');
 
 /**
  *  @서비스_알림_조회
@@ -43,7 +44,7 @@ module.exports = async (req, res) => {
       notice['noticeId'] = s.notificationId;
       notice['noticeTitle'] = s.title;
       notice['noticeContent'] = s.content;
-      notice['day'] = passedDay > 0 ? `${passedDay}일전` : `오늘`;
+      notice['day'] = passedDayToStr(passedDay);
       notice['isNew'] = !s.isRead;
       return notice;
     });
diff --git a/functions/api/routes/room/roomTimelineGET.js b/functions/api/routes/room/roomTimelineGET.js
index 875cd76..4eb1cb0 100644
--- a/functions/api/routes/room/roomTimelineGET.js
+++ b/functions/api/routes/room/roomTimelineGET.js
@@ -7,6 +7,7 @@ const { roomDB, lifeTimelineDB } = require('../../../db');
 const timelineMessage = require('../../../constants/lifeTimelineMessage');
 const slackAPI = require('../../../middlewares/slackAPI');
 const dayjs = require('dayjs');
+const { passedDayToStr } = require('../../../lib/passedDayToStr');
 
 /**
  *  @습관방_생명_타임라인_조회
@@ -63,7 +64,7 @@ module.exports = async (req, res) => {
       timeline['title'] = title;
       timeline['content'] = content;
       timeline['profiles'] = profiles;
-      timeline['day'] = passedDay > 0 ? `${passedDay}일전` : `오늘`;
+      timeline['day'] = passedDayToStr(passedDay);
       timeline['isNew'] = !t.isRead;
 
       return timeline;
diff --git a/functions/lib/passedDayToStr.js b/functions/lib/passedDayToStr.js
new file mode 100644
index 0000000..c9fea25
--- /dev/null
+++ b/functions/lib/passedDayToStr.js
@@ -0,0 +1,17 @@
+const passedDayToStr = (passedDay) => {
+  if (passedDay === 0) {
+    return '오늘';
+  }
+
+  if (passedDay < 7) {
+    return `${passedDay}일 전`;
+  }
+
+  if (passedDay < 30) {
+    return `${Math.floor(passedDay / 7)}주 전`;
+  }
+};
+
+module.exports = {
+  passedDayToStr,
+};