diff --git a/src/main/java/com/runtimematrix/service/RoleService.java b/src/main/java/com/runtimematrix/service/RoleService.java
new file mode 100644
index 0000000..28f61af
--- /dev/null
+++ b/src/main/java/com/runtimematrix/service/RoleService.java
@@ -0,0 +1,85 @@
+package com.runtimematrix.service;
+
+import com.runtimematrix.domain.exception.BusinessException;
+import com.runtimematrix.domain.model.Role;
+import com.runtimematrix.repository.RoleRepository;
+import com.runtimematrix.service.command.CreateRoleCommand;
+import com.runtimematrix.service.command.UpdateRoleCommand;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+
+/**
+ * 역할 관리 서비스.
+ * ADR-001 트랜잭션 경계: Service Layer public 메서드에서 시작
+ */
+@Service
+public class RoleService {
+
+    private static final Logger log = LoggerFactory.getLogger(RoleService.class);
+    private final RoleRepository roleRepository;
+
+    public RoleService(RoleRepository roleRepository) {
+        this.roleRepository = roleRepository;
+    }
+
+    /** 쓰기 트랜잭션 */
+    @Transactional
+    public Role createRole(CreateRoleCommand command) {
+        log.debug("Creating role: {}", command.name());
+        if (roleRepository.existsByName(command.name())) {
+            throw new BusinessException.RoleAlreadyExistsException(command.name());
+        }
+        Role role = Role.create(command.name(), command.description());
+        log.info("Role created: id={}, name={}", role.getId(), role.getName());
+        return roleRepository.save(role);
+    }
+
+    /** 읽기 전용 트랜잭션 */
+    @Transactional(readOnly = true)
+    public Role getRole(String roleId) {
+        log.debug("Fetching role: {}", roleId);
+        return roleRepository.findById(roleId)
+            .orElseThrow(() -> new BusinessException.RoleNotFoundException(roleId));
+    }
+
+    /** 읽기 전용 트랜잭션 */
+    @Transactional(readOnly = true)
+    public List<Role> getAllRoles() {
+        return roleRepository.findAll();
+    }
+
+    /** 쓰기 트랜잭션 */
+    @Transactional
+    public Role updateRole(String roleId, UpdateRoleCommand command) {
+        log.debug("Updating role: {}", roleId);
+        Role role = roleRepository.findById(roleId)
+            .orElseThrow(() -> new BusinessException.RoleNotFoundException(roleId));
+
+        if (command.name() != null && !command.name().equals(role.getName())) {
+            if (roleRepository.existsByName(command.name())) {
+                throw new BusinessException.RoleAlreadyExistsException(command.name());
+            }
+            role.updateName(command.name());
+        }
+        if (command.description() != null) {
+            role.updateDescription(command.description());
+        }
+        log.info("Role updated: id={}", roleId);
+        return role;
+    }
+
+    /** 쓰기 트랜잭션 */
+    @Transactional
+    public void deleteRole(String roleId) {
+        log.debug("Deleting role: {}", roleId);
+        if (!roleRepository.existsById(roleId)) {
+            throw new BusinessException.RoleNotFoundException(roleId);
+        }
+        roleRepository.deleteById(roleId);
+        log.info("Role deleted: id={}", roleId);
+    }
+}