The existing mobile service discovery approaches do not completely address the issues of service selection and the robustness faced to mobility. The infrastructure of mobile service must be QoS-aware plus context-aware (i.e.) aware of the user’s required-QoS and the QoS offered by the other networks in user’s context. In this paper, we propose a cluster based QoS-aware service discovery architecture using swarm intelligence. Initially, in this architecture, the client sends a service request together with its required QoS parameters like power, distance, CPU speed etc. to its source cluster head. Swarm intelligence is used to establish the intra and inter cluster shortest path routing. Each cluster head searches the QoS aware server with matching QoS constraints by means of a service table and a server table. The QoS aware server is selected to process the service request and to send the reply back to the client. By simulation results, we show that the proposed architecture can attain a good success rate with reduced delay and energy consumption, since it satisfies the QoS constraints.