An engine starting apparatus is provided which can start an engine without inducing malfunctions of various electronic components.The engine starting apparatus comprises a pinion adapted to be brought into meshing engagement with a ring gear linked to an engine, a magnet switch supplied with current from a battery to move the pinion in the direction of the ring gear, a starter motor supplied with the current to rotate the pinion, a control unit for instructing the starter motor to start the engine, and a starter control unit for controlling, on the basis of the instruction, a first semiconductor switch subject to PWM control, wherein the starter motor and the magnet switch are stored in a first housing, the starter control unit is stored in a second housing, and the first housing is integral with the second housing.