To obtain a silver halide photographic sensitive material for a photomechanical process having ultrahigh contrast and excellent in dot quality even in the case of a short exposure time by carrying out exposure under specific conditions and using a specified processing agent in processing using an automatic processing machine.

A silver halide photographic sensitive material having at least one silver halide emulsion layer on the substrate and containing 1×10-5-1×10-3 mol/m2 at least one hydrazine derivative in the emulsion layer is exposed by using an image setter and processed by using an automatic processing machine to obtain an image having a density of ≥4.5. In the exposure, 0.01-10 μJ/(sec/ cm2) exposure energy and 5×10-7-1×10-10 sec exposure time are adopted. In the processing using an automatic developer, a processing agent containing a compound of the formula as a developing agent but not substantially containing a hydroquinone derivative is used. In the formula, R11 and R12 are each alkyl or the like, (k) is 0 or 1, in the case of k=1, X is -CO- or the like and M1 and M2 are each H or an alkali metal.