Clustering is an important technique in mobile ad hoc networks to provide a framework for management and reduce the overhead of route acquisition. Many clustering techniques had been proposed in the literature, but few of them had considered the status of network from the aspect of stability. In this paper, a stability-based clustering (SBC) technique is proposed. SBC only constructs stable enough clusters to reduced maintenance overhead. Therefore, SBC tends to construct more clusters in low-mobility situations and fewer clusters in high-mobility situations. The route finding mechanism combining both unicasting and broadcasting of route request packets is proposed for SBC. Simulation study shows a better performance of SBC than Zone Routing Protocol, Lowest- ID Clustering, and Highest-Connectivity Clustering in terms of maintenance overhead and route finding cost.