A heat-shrinkable polyester film having a thermal shrinkage ratio of 15% or more in the longitudinal direction when treated at 100° C. for 10 seconds, a tensile strength at rupture in the longitudinal direction of 7 kgf/mm2 or more, and a difference between elongations at the hardening and yield points in the longitudinal direction of 15% or more exhibits superior properties, such as high tensile strength and crack-resistance in the longitudinal direction, suitable for labeling or shrink-wrapping containers.