PURPOSE: To obtain a highly shrinkable packaging film being highly shrinkable, almost free from slackness after shrinking packaging, capable of stretching at a lower temperature than conventional film, having large heating shrinkage factor and small natural shrinkage factor, excellent in flexibility and capable of providing a packaged article having beautiful package appearance.

CONSTITUTION: This highly shrinkable packaging film is a stretched film made of a resin composition containing (A) 5-60 pts.wt. 1-butene-based polymer, (B) 30-90 pts.wt. propylene-ethylene-based random copolymer, (C) 5-50 pts.wt. at least one resin selected from a petroleum resin, a hydrogenated petroleum resin and a terpene-type resin.