To provide a heat sensitive original plate for a planographic printing plate having good on-board developability in a case used as an on-board developing type, showing high sensitivity and high printing durability, having good antistaining properties or standing staining resistance (ink wiping properties) at the time of printing, capable of efficiently utilizing heat in the formation of an image in a case used as a conventional thermal positive or negative type, showing high sensitivity and high printing durability and hard to generate the staining of a non-image part.

The original plate for the planographic printing plate is constituted by providing a recording layer writable by the exposure to infrared laser on a support for the planographic printing plate obtained by forming an anodically oxidized film on an aluminum plate. In the cross section of the anodically oxidized film after the recording layer is provided, an atomic number ratio (C/Al) of carbon and aluminum due to Auger electron spectroscopic analysis is not more than 1.0.