A presensitized lithographic plate is comprised of a support base such as an aluminum support base with an anodized surface, having a subbing layer positioned thereon which is coated with a light-sensitive layer. The light-sensitive layer comprises a diazo compound and a binder or comprises a photopolymerizable composition. The subbing layer comprises a high molecular compound containing sulfonic acid group-containing monomer units as recurring units. The subbing layer provides a lithographic plate with greatly improved shelf life. Moreover, it increases the stability of the lithographic plate such that when the plate is stored it continues to be capable of producing copies which do not have stained background areas even when the plate is stored under adverse temperature and humidity conditions.