There is provided a drive unit which has high adhesive strength of its components and generates large drive power. The drive unit includes an electromechanical transducer, a driving friction member connected to an end surface of the electromechanical transducer and an engaging member engaging frictionally with the driving friction member. At least one end portion of the electromechanical transducer has a reduced cross-sectional area relative to a middle portion thereof.
