A resin blend composition of a polyamide resin and a polyester resin is described, which includes a polyamide resin, a polyester resin and an epoxy resin. The resin blend composition can have improved compatibility between the polyamide resin and the thermoplastic polyester resin, and therefore mechanical properties (strength, bending strength, elasticity, abrasion resistance, impact strength), chemical properties (solvent resistance), thermal resistance, dimensional stability, and paintability.