diff --git a/jobis-application/src/main/java/team/retum/jobis/domain/company/usecase/TeacherQueryCompaniesUseCase.java b/jobis-application/src/main/java/team/retum/jobis/domain/company/usecase/TeacherQueryCompaniesUseCase.java
index 403d55354..c92935ddd 100644
--- a/jobis-application/src/main/java/team/retum/jobis/domain/company/usecase/TeacherQueryCompaniesUseCase.java
+++ b/jobis-application/src/main/java/team/retum/jobis/domain/company/usecase/TeacherQueryCompaniesUseCase.java
@@ -77,7 +77,6 @@ public CompanyCountResponse countCompanies(
             .limit(1000)
             .build();
 
-
         return new CompanyCountResponse(
             queryCompanyPort.getByConditions(filter).stream().toList().size()
         );
diff --git a/jobis-application/src/main/java/team/retum/jobis/domain/file/model/FileType.java b/jobis-application/src/main/java/team/retum/jobis/domain/file/model/FileType.java
index 705c9f7a3..b49a66479 100644
--- a/jobis-application/src/main/java/team/retum/jobis/domain/file/model/FileType.java
+++ b/jobis-application/src/main/java/team/retum/jobis/domain/file/model/FileType.java
@@ -10,7 +10,7 @@
 public enum FileType {
 
     LOGO_IMAGE(List.of(".jpg", ".png", ".svg")),
-    EXTENSION_FILE(List.of(".pdf", ".ppt", ".pptx", ".hwp", ".jpg", ".png", ".zip", ".txt", ".mp4"));
+    EXTENSION_FILE(List.of(".pdf", ".ppt", ".pptx", ".hwp", ".jpg", ".png", ".zip", ".txt", ".mp4", ".opt", ".doc", ".docx", ".hwpx"));
 
     public final List<String> validExtensions;
 }
diff --git a/jobis-application/src/main/java/team/retum/jobis/domain/notice/dto/response/QueryNoticeDetailResponse.java b/jobis-application/src/main/java/team/retum/jobis/domain/notice/dto/response/QueryNoticeDetailResponse.java
index 21272b3c8..fc12eb6ce 100644
--- a/jobis-application/src/main/java/team/retum/jobis/domain/notice/dto/response/QueryNoticeDetailResponse.java
+++ b/jobis-application/src/main/java/team/retum/jobis/domain/notice/dto/response/QueryNoticeDetailResponse.java
@@ -6,6 +6,7 @@
 import team.retum.jobis.domain.notice.model.NoticeAttachment;
 
 import java.time.LocalDateTime;
+import java.util.ArrayList;
 import java.util.List;
 
 @Getter
diff --git a/jobis-application/src/main/java/team/retum/jobis/domain/notice/usecase/CreateNoticeUseCase.java b/jobis-application/src/main/java/team/retum/jobis/domain/notice/usecase/CreateNoticeUseCase.java
index 242c7040b..ef50e5135 100644
--- a/jobis-application/src/main/java/team/retum/jobis/domain/notice/usecase/CreateNoticeUseCase.java
+++ b/jobis-application/src/main/java/team/retum/jobis/domain/notice/usecase/CreateNoticeUseCase.java
@@ -9,6 +9,8 @@
 import team.retum.jobis.domain.notice.model.NoticeAttachment;
 import team.retum.jobis.domain.notice.spi.CommandNoticePort;
 
+import java.util.List;
+
 @RequiredArgsConstructor
 @UseCase
 public class CreateNoticeUseCase {
@@ -17,12 +19,15 @@ public class CreateNoticeUseCase {
     private final PublishEventPort publishEventPort;
 
     public void execute(CreateNoticeRequest request) {
+        List<NoticeAttachment> attachments = request.getAttachments().stream()
+            .filter(attachment -> attachment.getUrl() != null && attachment.getType() != null) // URL과 Type이 null이 아닌 경우만 필터링
+            .map(attachment -> new NoticeAttachment(attachment.getUrl(), attachment.getType()))
+            .toList();
+
         Notice savedNotice = commandNoticePort.save(Notice.builder()
             .title(request.getTitle())
             .content(request.getContent())
-            .attachments(request.getAttachments().stream()
-                .map(attachment -> new NoticeAttachment(attachment.getUrl(), attachment.getType()))
-                .toList())
+            .attachments(attachments)
             .build());
 
         publishEventPort.publishEvent(new NoticePostedEvent(savedNotice));
diff --git a/jobis-infrastructure/src/main/java/team/retum/jobis/domain/application/persistence/entity/ApplicationEntity.java b/jobis-infrastructure/src/main/java/team/retum/jobis/domain/application/persistence/entity/ApplicationEntity.java
index cdbcb9900..32a145ac2 100644
--- a/jobis-infrastructure/src/main/java/team/retum/jobis/domain/application/persistence/entity/ApplicationEntity.java
+++ b/jobis-infrastructure/src/main/java/team/retum/jobis/domain/application/persistence/entity/ApplicationEntity.java
@@ -64,7 +64,7 @@ public class ApplicationEntity extends BaseTimeEntity {
     @JoinColumn(name = "recruitment_id", nullable = false)
     private RecruitmentEntity recruitment;
 
-    @OneToMany(mappedBy = "application", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "application", cascade = CascadeType.ALL, orphanRemoval = true)
     private List<ApplicationAttachmentEntity> applicationAttachments = new ArrayList<>();
 
     @LastModifiedDate
diff --git a/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/persistence/mapper/NoticeMapper.java b/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/persistence/mapper/NoticeMapper.java
index 0624edfb8..2599e9797 100644
--- a/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/persistence/mapper/NoticeMapper.java
+++ b/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/persistence/mapper/NoticeMapper.java
@@ -14,9 +14,13 @@
 public class NoticeMapper {
 
     public NoticeEntity toEntity(Notice domain) {
-        List<NoticeAttachmentEntity> attachments = domain.getAttachments().stream()
-            .map(attachment -> new NoticeAttachmentEntity(attachment.getUrl(), attachment.getType()))
-            .toList();
+        List<NoticeAttachmentEntity> attachments = null;
+
+        if (domain.getAttachments() != null && !domain.getAttachments().isEmpty()) {
+            attachments = domain.getAttachments().stream()
+                .map(attachment -> new NoticeAttachmentEntity(attachment.getUrl(), attachment.getType()))
+                .toList();
+        }
 
         return NoticeEntity.builder()
             .id(domain.getId())
@@ -27,9 +31,13 @@ public NoticeEntity toEntity(Notice domain) {
     }
 
     public Notice toDomain(NoticeEntity entity) {
-        List<NoticeAttachment> attachments = entity.getAttachments().stream()
-            .map(attachment -> new NoticeAttachment(attachment.getAttachmentUrl(), attachment.getType()))
-            .toList();
+        List<NoticeAttachment> attachments = null;
+
+        if (entity.getAttachments() != null && !entity.getAttachments().isEmpty()) {
+            attachments = entity.getAttachments().stream()
+                .map(attachment -> new NoticeAttachment(attachment.getAttachmentUrl(), attachment.getType()))
+                .toList();
+        }
 
         return Notice.builder()
             .id(entity.getId())
diff --git a/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/presentation/dto/CreateNoticeWebRequest.java b/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/presentation/dto/CreateNoticeWebRequest.java
index f379ace3e..1ae9405c5 100644
--- a/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/presentation/dto/CreateNoticeWebRequest.java
+++ b/jobis-infrastructure/src/main/java/team/retum/jobis/domain/notice/presentation/dto/CreateNoticeWebRequest.java
@@ -35,10 +35,8 @@ public CreateNoticeRequest toDomainRequest() {
     @Getter
     public static class AttachmentWebRequest {
 
-        @NotBlank
         private String url;
 
-        @NotNull
         private AttachmentType type;
     }
 }