To provide an original film for a lithographic printing plate which is excellent in on-press developability and enables stable making of the lithographic printing plate having high sensitivity and high plate wear and which enables formation of an image by scanning exposure in a short time by a laser light or the like and can be made into the plate by a simple operation of water development or by direct fitting of the film on a press with no need of development.

Polymer particulates having an electric charge are electrodeposited on a substrate by impressing an electric field between a dispersion of the particulates and the substrate and thereby an image forming layer containing the polymer particulates is provided thereon. It is preferable that the polymer particulates are thermally weldable, that the dispersion is prepared by dispersing the particulates in an electrical insulating liquid and that the dispersion contains a photothermal conversion agent.