Abstract: In this study, an Energy-Aware Cluster-Based Routing (EACBR) protocol which adapts to the characteristics of WSAN is proposed. Sensors and actors are divided into some clusters and every cluster including an actor and some sensors is considered to different subnet. The Shortest Path Trees (SPTs) from sensors as resource to actor as destination in every subnet are calculated by Dijkstra algorithm. The process of EACBR protocol is divided into rounds and SPTs are dynamically generated according to network states in each round. The analysis and simulation results show that EACBR protocol can prolong network lifetime and reduce transmission delay.