An aluminum or aluminum alloy member superior in liquid and gaseous corrosion resistance and plasma resistance, which has an anodized film formed thereon which is composed of a porous layer and a non-porous barrier layer whose structure is at least partly boehmite or pseudo-boehmite. Said anodized film is characterized by that the film dissolving rate measured by the test for immersion in a mixture of phosphoric acid and chromic acid (conforming to JIS H8683-2) is less than 120 mg/dm2/15 min, the ratio of area in which corrosion occurs after standing for 2 hours in an atmosphere of argon containing 5% chlorine (at 300° C.) is less than 15%, and the hardness (Hv) of the film is no lower than 420.