Heat-shrinkable polyester-based film and packaged product

Provided is a heat-shrinkable polyester-based film which is heat-shrinkable in the longitudinal direction and which is freed from the above various problems, particularly the problem that curling-up or peeling occurs in a bonded area, and thus exhibits an excellent shrink finish. A heat-shrinkable polyester-based film in which the main shrinking direction is the longitudinal direction, characterized in that: the A1/A2 (absorbance) ratio in the longitudinal direction, which is the main shrinking direction of the film, is 0.55 to 1, while the A1/A2 ratio in the width direction perpendicular to the main shrinking direction is 0.5 to 0.9, A1 being the absorbance of the film at 1340cm-1 as determined by polarized ATR-FTIR spectroscopy, and A2 being the absorbance thereof at 1410cm-1 as determined thereby; and the hot-water shrinkage in the longitudinal direction of the film is 35 to 60%, while that in the width direction thereof is -3 to 12%, each hot-water shrinkage being determined by dipping the film in hot water at 90oC for 10 seconds.