A light-sensitive composition comprises a light-sensitive diazo resin, a polymer binder and a fluorine atom-containing surfactant, wherein the polymer binder is a polyurethane resin having acidic hydrogen atom- containing substituents and comprising structural units derived from a diol represented by the following general formula (I); and the fluorine atom-containing surfactant is a copolymer of (i) an acrylate or methacrylate having a fluoroaliphatic group which has a carbon atom number of 3 to 20 and a fluorine atom content of not less than 30% by weight and in which at least three terminal carbon atoms are completely fluorinated, with (ii) poly(oxyalkylene) acrylate or poly(oxyalkylene) methacrylate, the copolymer containing the fluoroaliphatic group- containing acrylate or methacrylate units in an amount ranging from 35 to 50% by weight on the basis of the weight of the copolymer and the copolymer having has a molecular weight ranging from 20,000 to 100, 000:PPHO--(CH.sub.2 CH.sub.2 O).sub.n --H (I)P Pwherein n is an integer of not less than 3. The light-sensitive composition can provide a PS plate having sufficient developability with an exhausted developer and can provide a lithographic printing plate having good printing durability and excellent ink receptivity during printing even after storing under high temperature and humidity conditions or after being exposed to light.
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