Flame-retardant resin composition and molding product formed of the same

A flame-retardant resin composition comprising (A) 100 parts by weight of a styrenic resin, (B) 1 to 30 parts by weight of one or more of phosphate ester compounds represented by the following formula (1), and (C) 0.1 to 10 parts by weight of one or more of phosphite ester compounds having a structure represented by the following formula (2) and having a long-chain alkyl group having 9 or more continuous carbon atoms in a molecule,

• wherein
• R1 to R8, which may be the same or different, each represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms,
• Y1 represents a direct bond, O , S, SO2, C(CH3)2, CH2 or CHPh. in which Ph represents a phenyl group,
• Ar1 to Ar4, which may be the same or different, each represents a phenyl group or a phenyl group substituted with a halogen-free organic residue,
• n is an integer of at least 0, and
• k and m are each an integer of at least 0 and at most 2, provided k+m is at least 0 and at most 2.