One aspect of the present invention pertains to a resin composition that comprises: a modified polyphenylene ether compound which is terminally modified with a substituent group having a carbon-carbon unsaturated double bond; a crosslink-type curing agent having a carbon-carbon unsaturated double bond in the molecule; a silane coupling agent having a phenyl amino group in the molecule; and silica, wherein the contained amount of the silica is 60-250 parts by mass with respect to 100 parts by mass of the sum of the modified polyphenylene ether compound and the crosslink-type curing agent.