To provide a method for manufacturing a tray vessel, which suppresses the functional deterioration (blushing, weakening sensitivity) of a heat developing photosensitive material, allows a customer to scrap the vessel after using it up without undergoing troublesome work of separating a combustible material from an incombustible material, and requires less cost in manufacturing the vessel in comparison with a conventional method.

The method is used to manufacture the tray vessel 2 in which a plurality of the heat developing photosensitive materials 1 are stored. The tray vessel 2 is manufactured by hot pressing a cardboard, using a die 11. Molding conditions upon molding the tray vessel 2 are such that the temperature of the die 11 is 180°C or higher, and the clamping pressure of the die 11 is 180 to 230 kgf/cm2 (18 to 23 Mpa).