To improve surface staining in printing and fine halftone dot reproducibility in printing when a material spectrally sensitized so as to ensure the sensitization maximum is the range of 610-710 nm and forming a planographic printing plate by a silver complex salt diffusion transfer process is preserved at a high humidity and a high temperature or when the material is subjected to running processing under a reduced replenishing amount.

The planographic printing plate material has its sensitization maximum in the range of 610-710 nm, contains ascorbic acid or a hydrazine derivative in a constituent layer and forms a planographic printing plate by a silver complex salt diffusion transfer process. A planographic printing plate material having its sensitization maximum in the range of 610-710 nm and forming a planographic printing plate by a silver complex salt diffusion transfer process is developed in the presence of ascorbic acid or a hydrazine derivative.