Disclosed is a light sensitive planographic printing plate material comprising a hydrophilic support and provided thereon, a light sensitve layer containing (A) an infrared absorbing dye, (B) a radical generating agent, and (C) a radically polymerizable compound, the light sensitve layer being an outermost layer, wherein the radical generating agent is selected from the group consisting of a sulfonium salt, a iodonium salt and a diazonium salt, and the radically polymerizable compound is a radically polymerizable oxirane compound having an oxirane ring in the molecule.