Conventional frequency control of the power system is realized by tracking varying loads through controlling the power output of generators.In recent years,many studies have shown that the demand response can better support the frequency control of power systems.However,the response delay and communication delay in the process of demand response can adversely affect the control results.This paper models the response delay and communication delay in the controlling process respectively,analyzes its influence on control results,and studies the influence of two kinds of delay on optimal control parameters in optimal control problem.The simulation analysis shows that the optimal control strategy can improve the control effect significantly.