ASP.NET Web Services Can be accessed only over HTTP but .Net Remoting Can be accessed over various protocols like TCP, HTTP, SMTP etc.
Web Services are based on stateless service architecture but .Net Remoting support for both stateful and stateless environment.
Web Services support heterogeneous environments means interoperability across platforms but .Net remoting requires .Net on both server and client end.
.NET Remoting provides the fast communication than Web Services when we use the TCP channel and the binary formatter.
Web services support only the objects that can be serialized but .NET Remoting can provide support to all objects that inherit MarshalByRefObject.
Web Services are reliable than .Net remoting because Web services are always hosted in IIS.
Web Services are ease to create and deploy but .Net remoting is bit complex to program.