First you need to be clear what a service is. Do you mean a single endpoint, or multiple endpoints in the same host?
Assuming you mean a single endpoint, then yes, but with a little work. An endpoint can only implement a single interface; so what you need to do is combine all the interfaces you want to implement into a single interface
public interface IMyInterface : IInterface1, IInterface2
and then implement them all inside your implementation class. What you cannot do is have multiple interfaces and multiple implementations magically merge into a single endpoint.