A distributed energy-balanced unequal clustering routing protocol (DEBUC) is proposed and evaluated in this paper, which adopts an unequal clustering mechanism in combination with an inter-cluster multihop routing. Through a time based competitive clustering algorithm, DEBUC partitions all nodes into clusters of unequal size, in which the clusters closer to the base station have smaller size. The cluster heads of these clusters can preserve some more energy for the inter-cluster relay traffic, and the “hot-spots” problem can be avoided. For inter-cluster communication, DEBUC adopts an energy-aware multihop routing system to reduce and balance the energy consumption of the cluster heads. Simulation results demonstrate that the protocol can efficiently decrease the dead speed of the nodes, balance the energy dissipation of all nodes, and prolong the network lifetime.