This paper describes the development and testing of an EAP (electroactive polymer) actuator for driving the wings of an MAV (micro air vehicle). Creating the drive system for a flapping MAV is extremely challenging because of the required combined bending/twisting of the wing during flapping. Silicone-based DEs (dielectric elastomer) were used for the actuator material. In addition, the EAP actuators were operated at resonant frequency which is an important means of producing optimal flight performance with reduced power consumption. The paper presents the optimisation of the structural and operational performance of the EAP actuator. The paper also presents the test results of the actuator driving an actual MAV wing.