diff --git a/transport/internet/kcp/receiving_test.go b/transport/internet/kcp/receiving_test.go
index 24d036578..1eff3977d 100644
--- a/transport/internet/kcp/receiving_test.go
+++ b/transport/internet/kcp/receiving_test.go
@@ -34,20 +34,3 @@ func TestRecivingWindow(t *testing.T) {
 	assert.Pointer(window.Remove(1)).Equals(seg2)
 	assert.Pointer(window.Remove(2)).Equals(seg3)
 }
-
-func TestACKList(t *testing.T) {
-	assert := assert.On(t)
-
-	ackList := new(ACKList)
-	ackList.Add(1, 2)
-	ackList.Add(3, 4)
-
-	seg := ackList.AsSegment()
-	assert.Byte(seg.Count).Equals(2)
-
-	ackList.Add(1, 3)
-	ackList.Clear(2)
-
-	seg = ackList.AsSegment()
-	assert.Byte(seg.Count).Equals(1)
-}