Abstract: A composite control method for actuated chambers of pneumatic microfluidic chips is proposed in this paper.The Bang-Bang,k+PWM and compound control methods are employed to analyze the step input signal.The pressure rise time,steady-state accuracy and pressure pulsation of the actuated chamber of the three closed-loop control methods are investigated and compared by experimental research.The composite control method of Bang-Bang+k+PWM combines the advantages of the Bang-Bang control and the k+PWM control:it reduces the response time of the actuated chamber,improves the steady-state accuracy and significantly reduces pressure fluctuations.