To provide a winning device capable of reliably preventing an outside fraudulent tool from contacting with drive means and transmission means, and a fraudulent act to leave a door fraudulently open.

A drive unit includes a solenoid having a plunger capable of operating forward and backward in the longitudinal direction in association with the forward and backward actions of the plunger thereby to move a door forward and backward. A casing includes: a bottom wall portion, on which the solenoid is arranged; a rear wall portion rising from the rear end portion of the bottom wall portion for closing the backs of the forward and backward moving ranges in the transverse directions of the plunger; and side wall portions rising from the side end portions on the side, at which the plunger in the bottom wall portion protrudes, for closing the sides of the leading ends of the plunger.