Abstract: The invention concerns a method for forming a coating with excellent adhesion, water resistance and appearance which comprises the combination of steps of applying on the hydrophobic surfaces having a surface tension of 35 dyne/cm or less of a substrate a dry surface treatment selected from vacuum plasma treatment, corona discharge treatment and ozonization treatment, coating thus treated surfaces with a dispersion type aqueous coating composition comprising an aqueous varnish of at least one aqueous resin whose 1 wt % deionized water solution has a surface tension of 51 dyne/cm or less and which has a water tolerance of 4 or more, and water insoluble resin uniformly dispersed in fine particles in said varnish, the water insoluble resin having a SP value which is 1.0 to 2.2 lower than that of said aqueous resin, and baking the coating. The present method is specifically useful in the coating of automobile bodies, appliances and other high-quality products.