PURPOSE: To obtain a composite material which gives a cured item excellent in flame retardance, dielectric characteristics, and heat resistance by combining a substrate with a resin compsn. comprising polyphenylene ether, a specific flame retardant, and a thermosetting monomer and/or a thermosetting resin.

CONSTITUTION: A curable polyphenylene ether resin compsn. is prepd. by compounding 100 pts.wt. compsn. comprising polyphenylene ether and at least one thermosetting monomer and/or a thermosetting resin with 5-100 pts.wt. compd. of the formula (wherein m and n are each 3-5 provided m+n is 8 or higher; and Z is a 4C or lower optionally brominated alkylene group). The compsn. is used for preparing a curable composite material contg. 5-90wt.% substrate. The material is molded and cured at 80-300°C under a pressure of 0.1-1000kg/cm2 for 1min to 10hr to give a cured composite material, which is laminated to a metal foil to give a resin laminate.