This study developed a diaphragm air liquid micro pump applicable to direct methanol fuel cells. Because direct methanol fuel cells use liquid methanol as fuel and the cathode terminal of the fuel cell uses an active air supply, improving the operational stability of the cell, general fuel cell systems are usually equipped with both liquid and air pumps. The overall consumed power will influence the output power of fuel cells; therefore, the output power can be increased using a pump that supplies both liquid and air. (C) 2013 Elsevier B.V. All rights reserved.