To provide a heat-shrinkable polyester film with excellent perforation cutting properties and straight line tearing properties.

An easily tearing film for heat-shrinkable packaging is characterized by a drawn film having a structure in which a polycarbonate incompatible to copolymerized polyester is dispersed in an insular strip in the copolymerized polyester, a haze of ≤20%, a shrinkage factor in hot water when it is treated for 10 sec in hot water of 80°C of ≥35% in the main shrinking direction and of ≤10% in the direction of intersecting at right angles to the main shrinking direction, and straight line tearing properties in the longitudinal direction.