Disclosed is a container cap having, as a sealing gasket, a layer of a resin composition as adhered to the surface of the cap body of polypropylene, wherein said resin composition comprises (A) from 25 to 70% by weight of an ethylene-vinyl alcohol copolymer having an ethylene content of from 20 to 60 mol % and a degree of saponification of at least 96% and (B) from 30 to 75% by weight of a polyolefin having a propylene or 1-butene content of at least 50 mol %. The container cap has excellent gas-barrier properties and sealability for containers, and is suitable for packaging containers for foods, medicines, agricultural chemicals, etc.