Abstract: An apparatus for performing a weather resistance test on a composite material having a metallic, inorganic, or organic base member, and an organic material covering the base member. The apparatus includes a sample holding device disposed in a sample chamber for holding a sample of the composite material. An artificial light source irradiates light substantially in the ultraviolet light area to one surface of the sample. A dipping mechanism dips the sample in a corrosive ionized water, and dew condensation is formed through a temperature control device disposed in the sample holding device, working with a moisture source, for causing dew condensation in the surface of the sample. A cleaning device is provided for cleaning the surface of the sample, and steaming of the sample is performed through the use of a heating element disposed in the sample chamber, and the moistening means, for steaming the sample in an atmosphere of high temperature and high humidity.