diff --git a/listener/inbound/trojan_test.go b/listener/inbound/trojan_test.go
index 5fd58491..0968243e 100644
--- a/listener/inbound/trojan_test.go
+++ b/listener/inbound/trojan_test.go
@@ -52,6 +52,9 @@ func testInboundTrojan(t *testing.T, inboundOptions inbound.TrojanOption, outbou
 
 	tunnel.DoTest(t, out)
 
+	if outboundOptions.Network == "grpc" { // don't test sing-mux over grpc
+		return
+	}
 	testSingMux(t, tunnel, out)
 }
 
diff --git a/listener/inbound/vless_test.go b/listener/inbound/vless_test.go
index 1052084f..56bab549 100644
--- a/listener/inbound/vless_test.go
+++ b/listener/inbound/vless_test.go
@@ -53,6 +53,9 @@ func testInboundVless(t *testing.T, inboundOptions inbound.VlessOption, outbound
 
 	tunnel.DoTest(t, out)
 
+	if outboundOptions.Network == "grpc" { // don't test sing-mux over grpc
+		return
+	}
 	testSingMux(t, tunnel, out)
 }
 
diff --git a/listener/inbound/vmess_test.go b/listener/inbound/vmess_test.go
index 58d23dfc..460cefb9 100644
--- a/listener/inbound/vmess_test.go
+++ b/listener/inbound/vmess_test.go
@@ -54,6 +54,9 @@ func testInboundVMess(t *testing.T, inboundOptions inbound.VmessOption, outbound
 
 	tunnel.DoTest(t, out)
 
+	if outboundOptions.Network == "grpc" { // don't test sing-mux over grpc
+		return
+	}
 	testSingMux(t, tunnel, out)
 }