Motor unit equipped with decelerator

A motor unit equipped with a decelerator, the motor unit comprising:

• a worm wheel provided in a wheel housing of a main body casing and rotatably supported around an axis;
• a motor fastened to the main body casing with a fastening member from one side orthogonal to the axis of the worm wheel and in which a worm fixed to an output shaft meshes with the worm wheel;
• a board housing defined by the main body casing so as to be adjacent to the wheel housing on the one side of the wheel housing;
• and
• a control board provided in the board housing in a posture of crossing an axis of the output shaft of the motor, electrically connected to the motor, and including, on the one side, a connector to be connected outside, wherein:
• the control board is inclined from a posture orthogonal to the axis of the output shaft of the motor toward a direction in which a position of an end portion on a motor side is displaced toward a side opposite to the one side, so that the end portion on the motor side is apart from a fastening portion including the fastening member in a direction of the axis of the output shaft.