disclosed herein is a flame retardant thermoplastic resin composition that has superior scratch resistance and mechanical properties , satisfying requirements for the appearance of housing materials resulting from a recent increase in volume of electrical and electronic products , and that contains a phosphorus - based flame - retarding agent , satisfying requirements for fire safety and prevention of environmental problems . the resin composition with scratch resistance comprises a base resin comprising about 30 to about 90 parts by weight of a polycarbonate resin , about 15 to about 50 parts by weight of a polymethylmethacrylate resin and about 5 to about 50 parts by weight of a polyethylene terephthalate - based resin , and about 5 to about 30 parts by weight of a phosphorus - based flame - retarding agent based on 100 parts by weight of the base resin . the composition may further comprise about 1 to about 30 parts by weight of an impact modifier based on 100 parts by weight of the base resin .