Abstract: A thermoplastic resin composition with improved impact resistance can include (A) about 30 to about 99 parts by weight of an epoxy group-containing styrenic polymer comprising (A1) about 5 to about 100% by weight of an epoxy group-containing vinyl copolymer containing about 0.001 to about 5.0 mol % of an epoxy compound; and (A2) about 0 to about 95% by weight of a rubber modified styrenic copolymer resin; (B) about 1 to about 70 parts by weight of a polyester resin; (C) about 0.001 to about 10 parts by weight of a silicone oil, per 100 parts by weight of a base resin comprising (A) and (B); (D) about 3 to about 20 parts by weight of a bromine-containing flame retardant, per 100 parts by weight of a base resin comprising (A) and (B); and (E) about 0.1 to about 6 parts by weight of a flame retardant aid, per 100 parts by weight of a base resin comprising (A) and (B).