To provide a snap fit slippage-preventing member capable of preventing a thrust fixed part from being slipped out by the falling or vibration in transportation.

In a snap fit mechanism for engaging locking the locking claws 3a and 84a of a feed roller 3 and a one-way clutch 84 in the separating unit 5a of a sheet carrying device to locking grooves 82a and 82b provided on the circumference of a feed shaft 82, this snap fit slippage-preventing member 85 is attachably and detachably mounted between the feed roller 3 and the one-way clutch 84. Since the thrust shaking W1 of the snap fit slippage-preventing member 85 is set narrower than the width W2 of a snap fit claw, the locking claws 3a and 84a can be prevented from being moved in the thrust direction and slipped out from the locking grooves 82a and 82b.