In order to solve the periodic hard real-time tasks with dependencies on multicore processors, the author proposes a low-power task scheduling algorithm for multicore processor systems based on the genetic algorithm. This method first uses the RDAG algorithm to separate the tasks and then takes the lowest power consumption as the principle; a genetic algorithm is used to determine the task mapping. Experimental results show that based on the power consumption model of Intel PXA270, several random task sets are used for simulation experiments, which shows that this method saves 20% to 30% of the energy consumption compared with the existing methods. This method effectively shortens the completion time of tasks, improves the utilization efficiency of multicore system resources, improves the parallel computing capability of multicore systems, reduces the average response time of tasks, and improves the throughput and resource utilization of multicore systems.