We propose a weight-based clustering routing protocol for wireless sensor networks. A new cluster head selection algorithm is developed in the proposed protocol. This algorithm aims at selecting better cluster heads in the network in order to minimise the energy dissipation of intra-cluster and inter-cluster data transmission. The load balance of the cluster heads is also considered when selecting cluster heads. The performance of the proposed protocol is evaluated and compared with two existing clustering-based protocols. Simulation results show that the proposed protocol achieves better energy efficiency and longer network lifetime.