Disclosed herein is a method of testing a corrosion resistance of a coated metal material including a surface treatment film on a metal substrate. The method includes: treatment of interposing a water-containing electrolyte material containing water, a supporting electrolyte, and a water penetration enhancer, between a surface of the surface treatment film of the coated metal material and an electrode; holding of the water-containing electrolyte material on the surface of the surface treatment film for one minute to one day; and electrical conduction from the electrode through the water-containing electrolyte material to the coated metal material.