The present invention provides an ethylene-hexafluoropropylene copolymer which is suitable as a hose or seal for engine oil of an automobile and has sufficient amine resistance, while maintaining heat resistance, oil resistance and chemical resistance close to that of conventional fluorine rubber. The ethylene-hexafluoropropylene copolymer comprises 35 to 60% by mole of ethylene structural unit, 25 to 50% by mole of hexafluoropropylene structural unit and 0 to 15% by mole of structural unit derived from a monomer copolymerizable therewith and has a fluorine content of at least 60% by weight and number average molecular weight of 3,000 to 500,000.