PURPOSE: To reduce the amount of a development intensifier used in development intensification and to prevent uneven development by spraying the development intensifier contg. H2O2 and a color developing agent and not contg. Br' and I' on an imagewise exposed photosensitive silver halide material.

CONSTITUTION: An imagewise exposed photosensitive silver halide material is subjected to development intensification by spraying a development intensifier contg. H2O2 or a compound releasing H2O2 and a color developing agent and not contg. Br' and I' on the silver halide material. The 1st soln. contg. the color developing agent and the 2nd soln. contg. H2O2 or a precursor thereof are separately prepd. The 1st and the 2nd solns. are sprayed simultaneously or successively, or they are mixed immediately before spraying and sprayed as a single soln. Since the solns. are separated, the exhaustion of the solns. by reaction is prevented. A pressure nozzle type or spraying type 1 is preferably used. By this spraying method, the development intensifier contains the color developing agent coexisting with H2O2, so the exhaustion of the intensifier is prevented, and the amount of the intensifier used can be reduced.