This invention relates to a polyester/polyamide blend having an excellent gas barrier property. More particularly, the present invention relates to combinations of a polyethylene terephthalate polymer and a polyamide polymer having an excellent gas barrier property and short oxygen scavenging induction periods, where the polyamide polymer has a C:A terminal group concentration ratio of 2:1 or more and a C+A terminal group concentration of at least 0.17 meq/g of polyamide polymer, wherein C represents a cumulative total of a terminal carboxyl group concentration and a terminal hydrocarbyl group concentration expressed in meq/g of polyamide, and A represents a terminal amine group concentration expressed in meq/g of polyamide.