The present invention provides a heat shrinkable polyester film whose hot water shrinkage along its main shrinkage direction is equal to or greater than 20% when the film is put in hot water of 70° C. for 5 sec; 35% to 55% when put in hot water of 75° C. for 5 sec; and 50% to 60% when put in hot water of 80° C. for 5 sec, wherein the compressive strength of the label formed by the film satisfies a following expression (1): Y>X2.2  (1) where y denotes compressive strength (mN) and x denotes film thickness (μm).