Disclosed are a planographic printing plate material and a planographic printing plate preparing process, the planographic printing plate material comprising a support and provided thereon, an image formation layer containing a colorant (a) having an absorption band in a wavelength region of from 700 to 1200 nm, a polymerization initiator (b) and a polymerizable ethylenically unsaturated compound (c), wherein the polymerization initiator (b) is a compound represented by the formula R.sup.1--CX.sub.2--(C.dbd.O)--R.sup.2.