A photodevelopable silver halide photosensitive material wherein a visible image is formed by a latent image-forming step in which high illumination exposure is effected for a short time and a subsequent light development step in which low illumination exposure is effected, which comprises at least one compound of the formula: ##STR1## wherein R.sub.1 is hydrogen, lower alkyl or a substituted or unsubstituted aryl group and salts thereof.