diff --git a/src/main/java/org/ntlab/acanthus_server/resources/gallery/InvitesRest.java b/src/main/java/org/ntlab/acanthus_server/resources/gallery/InvitesRest.java
index a8b54e7..b9f0805 100644
--- a/src/main/java/org/ntlab/acanthus_server/resources/gallery/InvitesRest.java
+++ b/src/main/java/org/ntlab/acanthus_server/resources/gallery/InvitesRest.java
@@ -12,6 +12,8 @@
 import javax.ws.rs.core.Response;
 import java.util.Collection;
 
+import static java.lang.Boolean.TRUE;
+
 @Component
 @Path("/gallery")
 
@@ -76,7 +78,7 @@
     @Path("/{aid}/invites")
     @PUT
     @Produces(MediaType.APPLICATION_JSON)
-    public String addInvite(@PathParam("aid") Integer aid, @FormParam("ownerUid") String ownerUid, @FormParam("invitedUid") String invitedUid, @FormParam("ownerToken") String ownerToken) {
+    public Boolean addInvite(@PathParam("aid") Integer aid, @FormParam("ownerUid") String ownerUid, @FormParam("invitedUid") String invitedUid, @FormParam("ownerToken") String ownerToken) {
         Animation animation = animations.getAnimationByAid(aid);
         Account invitedAccount = accounts.getAccountByUid(Integer.parseInt(invitedUid));
         Account owner = animation.getOwner();
@@ -107,7 +109,7 @@
             invitedAccount.getWorkHashMap().put(aid, work);
             invitedAccount.getWorkHashMap().get(aid).setInvites(animation);
 
-            return "追加しました";
+            return TRUE;
         } else {
             throw new WebApplicationException(404);
         }