To provide an additive composition for a color development processing liquid for a silver halide color photosensitive material having oxidative deterioration resistance and having high stability without varying the developability of a silver halide color photosensitive material after development processing, and also to provide a method for processing a silver halide color photosensitive material having excellent oxidative deterioration resistance.

The additive composition for a color development processing liquid for a silver halide color photosensitive material is the one to be added to a color development processing liquid used for forming the image of a silver halide color photosensitive material, and contains a compound expressed by general formula (1) by ≥15 mass%.