Heat-shrinkable polyester film and package

A heat-shrinkable polyester film comprising ethylene terephthalate as a main constituent component and containing 0 mol % or more and 5 mol % or less of a monomer component that can form an amorphous component in a whole polyester resin component, wherein the heat-shrinkable polyester film satisfies the following requirements (1) to (4):

• (1) the film has a hot-water heat shrinkage of 15% or more and 50% or less in a main shrinkage direction of the film when treated for 10 seconds in hot water of 90° C.;
• (2) the film has a hot-water heat shrinkage of 0% or more and 12% or less in a direction orthogonal to the main shrinkage direction of the film when treated for 10 seconds in hot water of 90° C.;
• (3) the film has a maximum shrinkage stress of 2 MPa or more and 10 MPa or less in the main shrinkage direction of the film when measured under hot air of 90° C.;
• and
• (4) the film contains 7 mol % or more and 30 mol % or less of a constituent unit derived from diethylene glycol in 100 mol % of the whole polyester resin component.