PURPOSE: To provide the titled compsn. having excellent moldability and resistance to impact and heat, by mixing a specified amide compd. with a polyphenylene ether or a mixture thereof with a styrene resin.

CONSTITUTION: 0.1W25wt% amide compd. of formula II [wherein R1, R2 are each a residue of a 1W10C straight chain or branched (un)saturated linear, alicyclic or arom. hydrocarbon or its derivative] and having an m.p. of 105W350°C and optionally 0.5W50wt% natural or synthetic rubbery elastomeric polymer or polymer having a sensitivity imparted thereto by introducing polar groups, are blended with a compsn. consisting of 100pts.wt. polyphenylene resin having a repeating unit of formula I (wherein Q is H, halogen, hydrocarbon group contg. no tertiary α-C, halohydrocarbon group contg. at least two C atoms between the halogen atom and the phenyl nucleus; n is at least 50) and 0W200pts.wt. styrene resin.