A composite of a resin member bonded to a vulcanized rubber member is obtained with using a rubber member vulcanized with a radical-generating agent (e.g., an
organic peroxide) and a
thermoplastic resin having at least 2 atoms, on average, selected from H and S atom per molecule, each atom having not less than 0.006 of an orbital
interaction energy coefficient S represented by the following formula (1):S=(CHOMO,n)2 / |Ec−EHOMO,n|+(CLUMO,n)2 / |Ec−ELUMO,n| (1)wherein Ec: an orbital energy (eV) of a radical, CHOMO,n: a molecular-orbital coefficient of a highest occupied
molecular orbital (HOMO) of an n-th H or S atom constituting a basic unit of the resin, EHOMO,n: an orbital energy (eV) of the HOMO, CLUMO,n: a molecular-orbital coefficient of a lowest unoccupied
molecular orbital (LUMO) of the n-th H or S atom constituting the basic unit of the resin, ELUMO,n: an orbital energy (eV) of the LUMO, and above all represent a value calculated by a semiempirical
molecular orbital method MOPACPM3. The
thermoplastic resin includes a
polyamide, a
polyester, a PPE, a POM, a PPS, a polyolefinic resins, and the unvulcanized rubber may comprise a
vulcanization-activating having plural polymerizable
unsaturated bonds. The invention gives the composite of the resin bonded directly to the rubber firmly without adhesives in wide combinations of the resin and the rubber.