A stretch-formed container having a layer comprising a blend of an ethylene terephthalate type polyester resin and another material, characterized in that the layer comprising the blend has a dispersion structure composed of a continuous phase comprising the ethylene terephthalate type polyester resin and a dispersed phase comprising the other material and that at least the container body part has a tan δ maximum temperature of 115° C. or lower in a dynamic viscoelasticity examination. Due to the constitution, even when the mechanical stretching rate reaches a limit, strain hardening effectively occurs. Thus, a stretch-formed container of a polyester resin can be provided which has both of excellent heat resistance attributable to high-temperature stretching and a stretch balance attributable to strain hardening.