To provide a self-timer device for a lens-fitted photographic film unit having a simple structure realizable at a low cost suitable to the cost of the lens-fitted photographic film unit, and having an adjusting function adapt able to various models without being limited to models of a specified maker.

The startup of rotating an eccentric cam with an extension part driven by the driving wheel of a spiral spring driving part is controlled by a shutter lever, and the shutter button of the camera is pushed by a shutter arm controlled by the expansion part coming with rotation after a lapse of required time, then, the leading end and terminal end of the expansion part are engaged with the shutter lever and the shutter arm, then, stopped.