diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/dto/request/OrgRequest.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/dto/request/OrgRequest.java
index c29ed56..6cb5d96 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/dto/request/OrgRequest.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/dto/request/OrgRequest.java
@@ -1,6 +1,9 @@
 package com.whereyouad.WhereYouAd.domains.organization.application.dto.request;
 
+import com.whereyouad.WhereYouAd.domains.organization.domain.constant.OrgRole;
+import io.swagger.v3.oas.annotations.media.Schema;
 import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.NotNull;
 
 public class OrgRequest {
 
@@ -22,4 +25,9 @@ public record Update (
             String logoUrl
     ) {}
 
+    public record UpdateRole (
+            @Schema(description = "조직 내 역할(ADMIN / MEMBER)", example = "ADMIN", allowableValues = {"ADMIN", "MEMBER"})
+            @NotNull(message = "역할은 필수입니다.")
+            OrgRole orgRole
+    ) {}
 }
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/mapper/OrgConverter.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/mapper/OrgConverter.java
index 4b47751..88c918b 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/mapper/OrgConverter.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/application/mapper/OrgConverter.java
@@ -66,6 +66,16 @@ public static Organization toOrganization(Long userId, OrgRequest.Create request
                 .build();
     }
 
+    // 단일 OrgMember -> OrgMemberDTO 변환
+    public static OrgResponse.OrgMemberDTO toOrgMemberDTO(OrgMember orgMember) {
+        return new OrgResponse.OrgMemberDTO(
+                orgMember.getUser().getName(),
+                orgMember.getUser().getEmail(),
+                orgMember.getUser().getProfileImageUrl(),
+                orgMember.getRole().name()
+        );
+    }
+
     // 조직 멤버 Slice DTO 변환 (무한 스크롤)
     public static OrgResponse.OrgMemberSliceDTO toOrgMemberSliceDTO(
             boolean hasNext,
@@ -73,12 +83,7 @@ public static OrgResponse.OrgMemberSliceDTO toOrgMemberSliceDTO(
             List<OrgMember> orgMembers
     ) {
         List<OrgResponse.OrgMemberDTO> memberDTOs = orgMembers.stream()
-                .map(m -> new OrgResponse.OrgMemberDTO(
-                        m.getUser().getName(),
-                        m.getUser().getEmail(),
-                        m.getUser().getProfileImageUrl(),
-                        m.getRole().name()
-                ))
+                .map(OrgConverter::toOrgMemberDTO)
                 .toList();
 
         return new OrgResponse.OrgMemberSliceDTO(
@@ -87,4 +92,4 @@ public static OrgResponse.OrgMemberSliceDTO toOrgMemberSliceDTO(
                 memberDTOs
         );
     }
-}
+}
\ No newline at end of file
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgService.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgService.java
index 0ae762f..c2e1909 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgService.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgService.java
@@ -21,4 +21,7 @@ public interface OrgService {
 
     // orgId 조직에서 memberId에 해당하는 맴버 제거
     void removeMemberFromOrg(Long userId, Long orgId, Long memberId);
+
+    // 조직 내 멤버 권한 변경 메서드
+    OrgResponse.OrgMemberDTO updateOrgMembersRole(Long userId, Long orgId, Long memberId, OrgRequest.UpdateRole dto);
 }
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgServiceImpl.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgServiceImpl.java
index 7033239..bcd702a 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgServiceImpl.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/domain/service/OrgServiceImpl.java
@@ -190,4 +190,34 @@ public void removeMemberFromOrg(Long userId, Long orgId, Long memberId) {
         // 5. 중간 테이블에서 해당 멤버 삭제
         orgMemberRepository.delete(targetMember);
     }
+
+    public OrgResponse.OrgMemberDTO updateOrgMembersRole(Long userId, Long orgId, Long memberId,
+            OrgRequest.UpdateRole dto) {
+
+        // 1. 조직 존재 여부 확인
+        Organization organization = orgRepository.findById(orgId)
+                .orElseThrow(() -> new OrgHandler(OrgErrorCode.ORG_NOT_FOUND));
+
+        // 2. 요청자가 해당 조직의 ADMIN인지 확인
+        OrgMember requester = orgMemberRepository.findByUserIdAndOrgId(userId, orgId)
+                .orElseThrow(() -> new OrgHandler(OrgErrorCode.ORG_MEMBER_NOT_FOUND));
+
+        if (requester.getRole() != OrgRole.ADMIN) {
+            throw new OrgHandler(OrgErrorCode.ORG_MEMBER_FORBIDDEN);
+        }
+
+        // 3. 해당 조직 내 멤버 조회 (상대방도 ADMIN이라면 MEMBER로 변경 불가)
+        OrgMember orgMember = orgMemberRepository.findByUserIdAndOrgId(memberId, orgId)
+                .orElseThrow(() -> new OrgHandler(OrgErrorCode.ORG_MEMBER_NOT_FOUND));
+
+        if (orgMember.getRole() == OrgRole.ADMIN) {
+            throw new OrgHandler(OrgErrorCode.ORG_CANNOT_ADMIN_TO_MEMBER);
+        }
+
+        // 역할 변경 (더티체킹)
+        orgMember.updateRole(dto.orgRole());
+
+        // 변경된 멤버 정보를 DTO 로 반환
+        return OrgConverter.toOrgMemberDTO(orgMember);
+    }
 }
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/exception/code/OrgErrorCode.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/exception/code/OrgErrorCode.java
index fca280f..d2fa7ec 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/exception/code/OrgErrorCode.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/exception/code/OrgErrorCode.java
@@ -12,6 +12,7 @@ public enum OrgErrorCode implements BaseErrorCode {
     ORG_NAME_DUPLICATE(HttpStatus.BAD_REQUEST, "ORG_400_1", "사용자가 이미 속해있는 조직의 이름입니다."),
     ORG_CANNOT_KICK_SELF(HttpStatus.BAD_REQUEST, "ORG_400_2", "자기 자신을 추방할 수 없습니다."),
     ORG_CANNOT_KICK_ADMIN(HttpStatus.BAD_REQUEST, "ORG_400_3", "ADMIN은 추방할 수 없습니다."),
+    ORG_CANNOT_ADMIN_TO_MEMBER(HttpStatus.BAD_REQUEST, "ORG_400_4", "ADMIN은 MEMBER로 변경할 수 없습니다."),
 
     // 403
     ORG_FORBIDDEN(HttpStatus.FORBIDDEN, "ORG_403_1", "해당 요청은 조직 생성자만 요청 가능합니다."),
@@ -24,7 +25,6 @@ public enum OrgErrorCode implements BaseErrorCode {
     //409
     ORG_ALREADY_ACTIVE(HttpStatus.CONFLICT, "ORG_409_1", "해당 조직은 이미 활성화 상태 입니다."),
 
-
     //410
     ORG_SOFT_DELETED(HttpStatus.GONE, "ORG_410_1", "해당 조직은 삭제된 조직입니다.(Soft Delete)"),
     ;
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/entity/OrgMember.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/entity/OrgMember.java
index cee7b65..b023a18 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/entity/OrgMember.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/entity/OrgMember.java
@@ -34,4 +34,8 @@ public class OrgMember { //중간 테이블이므로 BaseEntity 미적용
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "org_id")
     private Organization organization;
+
+    public void updateRole(OrgRole role) {
+        this.role = role;
+    }
 }
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/repository/OrgMemberRepository.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/repository/OrgMemberRepository.java
index c3ac8f5..749d7f9 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/repository/OrgMemberRepository.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/persistence/repository/OrgMemberRepository.java
@@ -17,14 +17,7 @@ public interface OrgMemberRepository extends JpaRepository<OrgMember, Long> {
 
     //User 가 가진 OrgMember 모두 추출하는 메서드
     List<OrgMember> findOrgMemberByUser(User user);
-
-    // userId 와 orgId 로 특정 OrgMember 조회
-    @Query("SELECT om FROM OrgMember om " +
-            "WHERE om.user.id = :userId " +
-            "AND om.organization.id = :orgId " +
-            "AND om.user.status = 'ACTIVE'")
-    Optional<OrgMember> findByUserIdAndOrgId(@Param("userId") Long userId, @Param("orgId") Long orgId);
-
+    
     //userId 를 통해 OrgMember 추출 -> Organization 의 status 가 ACTIVE 인 경우에만 조회
     @Query(value = "select om from OrgMember om join fetch om.organization o where om.user.id = :userId and o.status = 'ACTIVE'")
     List<OrgMember> findOrgMemberByUserId(@Param("userId") Long userId);
@@ -47,6 +40,13 @@ Slice<OrgMember> findByOrganizationIdWithCursor(
             Pageable pageable
     );
 
+    // userId 와 orgId 로 특정 OrgMember 조회
+    @Query("SELECT om FROM OrgMember om " +
+            "WHERE om.user.id = :userId " +
+            "AND om.organization.id = :orgId " +
+            "AND om.user.status = 'ACTIVE'")
+    Optional<OrgMember> findByUserIdAndOrgId(@Param("userId") Long userId, @Param("orgId") Long orgId);
+
     // 조직의 전체 멤버 수 조회
     @Query("SELECT COUNT(m) FROM OrgMember m " +
             "JOIN m.user u " +
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/OrgController.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/OrgController.java
index 77b8ded..f8474f0 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/OrgController.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/OrgController.java
@@ -125,4 +125,15 @@ public ResponseEntity<DataResponse<String>> removeMember(
         orgService.removeMemberFromOrg(userId, orgId, memberId);
         return ResponseEntity.ok(DataResponse.from("해당 맴버가 조직에서 제외되었습니다."));
     }
+
+    @PatchMapping("/members/{orgId}/{memberId}")
+    public ResponseEntity<DataResponse<OrgResponse.OrgMemberDTO>> updateOrgMembersRole(
+            @AuthenticationPrincipal(expression = "userId") Long userId,
+            @PathVariable Long orgId,
+            @PathVariable Long memberId,
+            @RequestBody OrgRequest.UpdateRole dto
+    ) {
+        OrgResponse.OrgMemberDTO response = orgService.updateOrgMembersRole(userId, orgId, memberId, dto);
+        return ResponseEntity.ok(DataResponse.from(response));
+    }
 }
\ No newline at end of file
diff --git a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/docs/OrgControllerDocs.java b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/docs/OrgControllerDocs.java
index f6269a5..e73d578 100644
--- a/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/docs/OrgControllerDocs.java
+++ b/src/main/java/com/whereyouad/WhereYouAd/domains/organization/presentation/docs/OrgControllerDocs.java
@@ -134,4 +134,21 @@ public ResponseEntity<DataResponse<String>> removeMember(
             @PathVariable Long orgId,
             @PathVariable Long memberId
     );
+
+    @Operation(
+            summary = "조직 맴버 권한 변경 API",
+            description = "맴버 권한 변경을 요청한 유저의 권한이 ADMIN인 경우 실행이 가능합니다. memberId에 해당하는 맴버의 권한을 변경시킵니다."
+    )
+    @ApiResponses({
+            @ApiResponse(responseCode = "200", description = "성공 (totalCount: 전체 멤버 수)"),
+            @ApiResponse(responseCode = "401", description = "잘못된 요청을 보낸 경우(ADMIN의 권한 변경)"),
+            @ApiResponse(responseCode = "403", description = "권한이 부족한 경우(요청을 보낸 유저의 권한이 ADMIN이 아닌 경우)"),
+            @ApiResponse(responseCode = "404", description = "해당 id의 데이터 존재 X")
+    })
+    ResponseEntity<DataResponse<OrgResponse.OrgMemberDTO>> updateOrgMembersRole(
+            @AuthenticationPrincipal(expression = "userId") Long userId,
+            @PathVariable Long orgId,
+            @PathVariable Long memberId,
+            @RequestBody OrgRequest.UpdateRole dto
+    );
 }
\ No newline at end of file