In order to improve the performance of networked control system, this paper proposed a dynamic weight variable sampling period scheduling algorithm for networked control system. Firstly, each controlled loop weight is dynamically adjusted according to controlled loop data transmission error through quadratic square root mapping function, the different weight is given for each loop. Then the prediction of the new network utilization through proportional control is given based on the current network status, and least square support vector machine algorithm (LSSVM) is used for controlled loop packet transmission time prediction. Finally, under certain conditions of the network bandwidth limitation, variable sampling time for each controlled loop is determined by using dynamic weight of the controlled loop, network utilization and data transmission time, thus the system performance is optimized. The simulation results show that under the proposed variable sampling periodical scheduling algorithm, the network utilization converges to the setting value, the delay of control loop data transmission is reduced, and the output response performance and control performance of the system are improved.