A thermoplastic resin composition is disclosed which comprises
(a) a modified polyphenylene ether or a composition containing it, and
(b) (i) a modified propylene polymer comprising propylene polymer which is graft-copolymerized with a styrene based monomer or with a mixture of a styrene based monomer and a monomer copolymerizable therewith, or (ii) a composition containing the modified propylene polymer in (b)-(i) and propylene polymer. The resin composition may contain (c) a rubber-like substance containing at least one rubber-like substance having a polar group and/or (d) a melt flow characteristics improving agent.