diff --git a/src/main/kotlin/com/example/boheom/domain/feed/exception/ImpossibleApplicationException.kt b/src/main/kotlin/com/example/boheom/domain/feed/exception/ImpossibleApplicationException.kt
new file mode 100644
index 0000000..1acb09f
--- /dev/null
+++ b/src/main/kotlin/com/example/boheom/domain/feed/exception/ImpossibleApplicationException.kt
@@ -0,0 +1,6 @@
+package com.example.boheom.domain.feed.exception
+
+import com.example.boheom.global.error.exception.BoheomException
+import com.example.boheom.global.error.exception.ErrorCode.IMPOSSIBLE_APPLICATION
+
+object ImpossibleApplicationException: BoheomException(IMPOSSIBLE_APPLICATION)
\ No newline at end of file
diff --git a/src/main/kotlin/com/example/boheom/domain/feed/service/FeedApplyService.kt b/src/main/kotlin/com/example/boheom/domain/feed/service/FeedApplyService.kt
index b14c90e..a3c7068 100644
--- a/src/main/kotlin/com/example/boheom/domain/feed/service/FeedApplyService.kt
+++ b/src/main/kotlin/com/example/boheom/domain/feed/service/FeedApplyService.kt
@@ -1,10 +1,13 @@
 package com.example.boheom.domain.feed.service
 
 import com.example.boheom.domain.feed.domain.Apply
+import com.example.boheom.domain.feed.domain.Feed
 import com.example.boheom.domain.feed.domain.repository.ApplyRepository
 import com.example.boheom.domain.feed.exception.AlreadyApplyException
+import com.example.boheom.domain.feed.exception.ImpossibleApplicationException
 import com.example.boheom.domain.feed.exception.NotAllowSelfApplicationException
 import com.example.boheom.domain.feed.facade.FeedFacade
+import com.example.boheom.domain.user.domain.User
 import com.example.boheom.domain.user.facade.UserFacade
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Transactional
@@ -20,12 +23,20 @@ class FeedApplyService(
     fun execute(feedId: UUID) {
         val user = userFacade.getCurrentUser()
         val feed = feedFacade.getByFeedId(feedId)
+        validateApply(feed, user)
+        applyRepository.save(Apply(user, feed))
+    }
+    fun validateApply(feed: Feed, user: User) {
+        val applyCount = applyRepository.countByFeed(feed)
+
         if (user.equals(feed.user)) {
             throw NotAllowSelfApplicationException
         }
         if (applyRepository.existsByUserAndFeed(user, feed)) {
             throw AlreadyApplyException
         }
-        applyRepository.save(Apply(user, feed))
+        if (feed.recruitment.equals(applyCount)) {
+            throw ImpossibleApplicationException
+        }
     }
 }
\ No newline at end of file
diff --git a/src/main/kotlin/com/example/boheom/global/error/exception/ErrorCode.kt b/src/main/kotlin/com/example/boheom/global/error/exception/ErrorCode.kt
index d387045..10d9265 100644
--- a/src/main/kotlin/com/example/boheom/global/error/exception/ErrorCode.kt
+++ b/src/main/kotlin/com/example/boheom/global/error/exception/ErrorCode.kt
@@ -9,6 +9,7 @@ enum class ErrorCode(
     INCORRECT_USER(400, "Incorrect User"),
     NOT_ALLOW_SELF_APPLICATION(400, "Not Allow Self Application"),
     BAD_FILE_EXTENSION(400, "Bad File Extension"),
+    IMPOSSIBLE_APPLICATION(400, "Impossible Application"),
 
     TOKEN_INVALID(401, "Token Invalid"),
     TOKEN_EXPIRED(401, "Token Expired"),