The present invention provides a photosensitive composition including a compound that generates a radical by application of light or heat, a polymer having a phenyl group substituted with a vinyl group on the side chain, a monomer having two or more phenyl groups substituted with a vinyl group, an infrared absorbing agent, and a compound having at least one carboxylic acid group and a weight average molecular weight of 3,000 or less. Additionally, the invention provides a planographic printing plate precursor including a substrate and a negative recording layer provided on the substrate and containing the above photosensitive composition.