A drive apparatus includes a power module, a connector and a heat sink. The connector is used for electric connection to an external side and has a flange, which is formed on its peripheral wall. The heat sink is formed to have a module holding part for holding the power module and a fitting hole for fitting with the flange and has a connector holding part for holding a connector. The flange is formed along a first surface, which faces the connector holding part of the peripheral wall, and side surfaces, which are formed on both sides of the first surface. Thus, water droplets are prevented from entering into a control unit through a clearance between the connector and the heat sink without adding other members such as a water preventing cover.