To provide an automatic development processor which gets along with a small quantity of developer, etc., and does not cause uneven development and uneven processing even in large-sized photosensitive material.

This automatic processor is provided with a photosensitive material conveying means which holds the photosensitive material and conveys the same in one direction, a processing solution applying part which applies the processing solution on a photosensitive surface of the photosensitive material which is conveyed by the photosensitive material conveying means and a heating processing part which heats the photosensitive surface on which the processing solution is applied. Therein, the heating processing part is provided with a far infrared radiation means which radiates far infrared radiation on the photosensitive surface and a radiation intensity uniformizing means which is disposed near the far infrared radiation means and uniformizes the intensity of far infrared radiation which is radiated on the photosensitive surface.