diff --git a/src/main/java/ollie/wecare/challenge/entity/Challenge.java b/src/main/java/ollie/wecare/challenge/entity/Challenge.java
index 229d3a0..83b8216 100644
--- a/src/main/java/ollie/wecare/challenge/entity/Challenge.java
+++ b/src/main/java/ollie/wecare/challenge/entity/Challenge.java
@@ -22,6 +22,9 @@ public class Challenge extends BaseEntity {
     public void updateAttendanceCode(String attendanceCode) {
         this.attendanceCode = attendanceCode;
     }
+    public void updateAttendanceRate(Integer attendanceRate) {
+        this.attendanceRate = attendanceRate;
+    }
 
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
diff --git a/src/main/java/ollie/wecare/challenge/service/ChallengeService.java b/src/main/java/ollie/wecare/challenge/service/ChallengeService.java
index a34e12e..94a46a4 100644
--- a/src/main/java/ollie/wecare/challenge/service/ChallengeService.java
+++ b/src/main/java/ollie/wecare/challenge/service/ChallengeService.java
@@ -77,6 +77,9 @@ public void attendChallenge(AttendChallengeReq attendChallengeReq) throws BaseEx
                     .challenge(challengeRepository.findById(attendChallengeReq.getChallengeIdx()).orElseThrow(()-> new BaseException(INVALID_CHALLENGE_IDX)))
                     .build();
             challengeAttendanceRepository.save(challengeAttendance);
+            Integer newAttendanceRate = (int) ((challenge.getAttendanceRate()/(float)100 + (1/(float)((challenge.getTotalNum()) * challenge.getParticipants().size()))) * 100);
+            //log.info("attendanceRate : {}", newAttendanceRate);
+            challenge.updateAttendanceRate(newAttendanceRate);
         }
     }
 
@@ -128,8 +131,9 @@ private static DateDto convertToDateDto(LocalDateTime dateTime) {
     // 챌린지 개인 달성률 계산
     private Integer calculateMyAchievementRate(User user, Challenge challenge) {
         Integer attendanceCount = challengeAttendanceRepository.countByUserAndChallenge(user, challenge);
+        log.info("attendanceCount : {}", attendanceCount);
         if (attendanceCount == null) return 0;
-        else return (attendanceCount/challenge.getTotalNum()) * 100;
+        else return (int)((attendanceCount/(float)challenge.getTotalNum()) * 100);
     }
 
     /*
diff --git a/src/main/java/ollie/wecare/program/service/ProgramService.java b/src/main/java/ollie/wecare/program/service/ProgramService.java
index c3046bd..1e19682 100644
--- a/src/main/java/ollie/wecare/program/service/ProgramService.java
+++ b/src/main/java/ollie/wecare/program/service/ProgramService.java
@@ -21,6 +21,7 @@
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.time.Duration;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.time.LocalTime;
@@ -81,7 +82,9 @@ public void saveTag(PostProgramReq postProgramReq, Program program) {
     }
 
     public Challenge saveChallenge(Program program, User user) {
+        Duration duration = Duration.between(program.getOpenDate(), program.getDueDate());
+        Integer totalNum = Math.toIntExact(duration.toDays() / 7);//TODO : 특정 요일 횟수 반영
         return challengeRepository.save(Challenge.builder().program(program).name(program.getName()).attendanceRate(0)
-                .admin(user).host(program.getHost()).totalNum(10).build());
+                .admin(user).host(program.getHost()).totalNum(totalNum).build());
     }
 }