By a method of preparing a lithographic printing plate having exposing a lithographic printing plate precursor including a photosensitive layer containing (A) a polymerization initiator, (B) a polymerizable compound, (C) a sensitizing dye and (D) a binder polymer and a protective layer in this order on a hydrophilic support with laser and then removing the protective layer and an unexposed area of the photosensitive layer in the presence of a developer, in which the developer is a developer which has pH of from 2 to less than 10 and contains an amphoteric surfactant and a nonionic surfactant having an alkylene oxide chain, a simple processing of one solution and one step which does not require a water washing step becomes possible, excellent development property is achieved and a lithographic printing plate which has good printing durability and does not cause printing stain can be provided.