To form a black-and-white image low in Dmin, high in sensitivity and gradation and sharpness and image quantity, in a short time without using any developer and to enhance the storage stability of raw stock and the film quantity of the photosensitive material.

The black-and-white image is formed by exposing a silver halide photographic sensitive material having a photosensitive silver halide emulsion, a hydrophilic binder, and a basic metal compound hardly soluble in water, and overlaying this material on a processing sheet containing a complex-forming compound with the metal ion of the above basic metal compound, physical development nuclei, a silver halide solvent after the exposure or at the time of it, heat developing is executed in the presence of a reducing agent and water to form a silver image is this photosensitive material. At that time, a hydrophilic colloidal layer containing an amount of a binder of 0.1-1g/m2 and no fine solid dispersed grain is provided under the emulsion layer of the photosensitive material on the side of the support.