PURPOSE: To obtain a composition free of dripping tendency in combustion and having low smoking tendency and excellent flame-retardancy, by compounding a halogen-free copolymer resin composed mainly of ethylene with red phosphorus and a mixture of aluminum hydroxide and magnesium hydroxide.

CONSTITUTION: The objective composition can be produced by compounding (A) 100pts. (wt.) of a halogen-free copolymer resin composed mainly of ethylene with (B) 50W150pts. of a hydrated inorganic compound composed of 5W80wt% aluminum hydroxide and 95W20wt% magnesium hydroxide and (C) 2W50pts. of red phosphorus. The aluminum hydroxide and magnesium hydroxide are preferably surface-treated before compounding. The component C is produced by coating the surface of fine red phosphorus particles with a resin, etc.