diff --git a/src/main/kotlin/dev/usbharu/hideout/activitypub/service/activity/undo/APUndoProcessor.kt b/src/main/kotlin/dev/usbharu/hideout/activitypub/service/activity/undo/APUndoProcessor.kt
index 21734428..010766cb 100644
--- a/src/main/kotlin/dev/usbharu/hideout/activitypub/service/activity/undo/APUndoProcessor.kt
+++ b/src/main/kotlin/dev/usbharu/hideout/activitypub/service/activity/undo/APUndoProcessor.kt
@@ -1,8 +1,10 @@
 package dev.usbharu.hideout.activitypub.service.activity.undo
 
+import dev.usbharu.hideout.activitypub.domain.model.Accept
 import dev.usbharu.hideout.activitypub.domain.model.Block
 import dev.usbharu.hideout.activitypub.domain.model.Follow
 import dev.usbharu.hideout.activitypub.domain.model.Undo
+import dev.usbharu.hideout.activitypub.domain.model.objects.ObjectValue
 import dev.usbharu.hideout.activitypub.service.common.AbstractActivityPubProcessor
 import dev.usbharu.hideout.activitypub.service.common.ActivityPubProcessContext
 import dev.usbharu.hideout.activitypub.service.common.ActivityType
@@ -50,6 +52,25 @@ class APUndoProcessor(
                 return
             }
 
+            "Accept" -> {
+                val accept = undo.apObject as Accept
+
+
+                val acceptObject = if (accept.apObject is ObjectValue) {
+                    accept.apObject.`object`
+                } else if (accept.apObject is Follow) {
+                    accept.apObject.apObject
+                } else {
+                    logger.warn("FAILED Unsupported type. Undo Accept {}", accept.apObject.type)
+                    return
+                }
+
+                val accepter = apUserService.fetchPersonWithEntity(undo.actor, acceptObject).second
+                val target = userQueryService.findByUrl(acceptObject)
+
+                relationshipService.rejectFollowRequest(accepter.id, target.id)
+            }
+
             else -> {}
         }
         TODO()