<p>Disclosed is polyester resin for use in blending capable of providing a polyester blend which has a moderate crystallization rate and can be used favorably for molding a heat-resistant container or the like by being blended with a polyester resin having a low crystallization rate. The polyester resin for use in blending is a polyester resin which has a terminal carboxyl group concentration ranging from 20 to 50 eq/ton and is obtained by preparing a polyester resin having an intrinsic viscosity ranging from 0.80 to 1.0 dL/g by liquid- and solid-phase polymerization, and then decreasing the intrinsic viscosity of the polyester resin to 0.3 to 0.75 dL/g.</p>
