Abstract: Due to the drawbacks in energy efficient and low-latency of the most of wireless sensor MAC scheduling algorithm，an Adaptive Time-slot Scheduling Algorithm（ATSA） based on clustering is presented.ATSA divided the entire network into some clusters，the algorithm combines with the information of the routing，it can obviously reduce the energy consumption，the cluster head adjusts the time-slot of nodes according to their real-time traffic load in a proper order and frequency，thus the idle listening is reduced，and the energy consumption balancing among nodes is achieved with a low latency.Simulation results show that the algorithm can meet the system requirements in reliability，real-time response and energy efficiency.