A method for preparing a lithographic printing plate comprising the steps of imagewise exposing, to light, a presensitized plate for use in making a lithographic printing plate, which comprises a grained and anodized substrate provided thereon with a photopolymerizable light-sensitive layer containing a compound having at least one addition-polymerizable ethylenically unsaturated double bond and a titanocene type initiator; and then developing the light-exposed presensitized plate using a developer which comprises a surfactant and a weak acid or a salt thereof having a dissociation constant pka ranging from 10 to 13, and has a pH value ranging from 11.5 to 12.8. The method exhibits excellent development performance, and gives good results to the resultant printing plate in terms of printing durability and scumming. In addition, the change in pH value of the developer is so small that the stable development can be ensured for a long period of time.