PURPOSE: To make it possible to easily form various print original forms, by drawing the reverse image of a picture or character on a heat resistant original form base material by foamable ink expanding by heating and applying heat treatment to said image.

CONSTITUTION: The reverse image of a desired picture or character 4 is drawn on a heat resistant original form base material 3 by foamable ink expanding by heating and hot air of 100°C or less is subsequently blown to said reverse image to evaporate the org. solvent in the foamable ink while the dried image is heated to 100W140°C for at least 30 sec or more to be expanded through the foaming of the ink. The picture or character is expanded by heat treatment to be further largely expanded from the picture on the original form base mate rial and, even if stamp ink or paint is applied to the expanded reverse image, the surface of the original form base material is not colored and the ink or paint on the reverse image can be transferred to desired paper. By this method, a print original plate rich in taste and individuality can be easily formed.