Polyester container having excellent heat resistance and shock resistance and method of producing the same

A polyester container obtained by stretch-forming a preform of a thermoplastic polyester resin formed by injection forming wherein the central portion of the bottom wall is the remaining part of the gate at the time of injection forming, and is formed relatively thicker than the bottom wall surrounding the central portion, and the central portion of the bottom wall is substantially amorphous, and the bottom wall surrounding the central portion is oriented and crystallized. The container exhibits excellent heat resistance and shock resistance despite a thick portion that is the remaining portion of the injection gate is formed at the center of the bottom portion.