To provide a photosensitive material treatment apparatus that can obtain a press plate that improves defective development of a photo sensitive material having a flexibility support medium, and is excellent in plate life.

A photosensitive material treatment apparatus includes: a transportation means that transports a photo sensitive material; a developing acceleration means that contacts a photosensitive face of a photo sensitive material, and revolves by peripheral velocity faster than a transportation speed of a photo sensitive material in the same direction as the transportation direction; a back-up roller that is disposed at an opposite side of a photosensitive face of a photo sensitive material, and contacts the developing acceleration means; and a thin plate guide which has a wider width than that of a photo sensitive material downstream of a developing acceleration means.