PURPOSE: To obtain an ultraviolet-curing resin compsn. which is excellent in flexibility and adhesion to a conductor without lowering the heat resistance and is useful for electric wire sheathing, heat-resistant film, etc.

CONSTITUTION: The title compsn. comprises (A) a polyethylene terephthalate resin having a melting point of above 170°C, (B) a satd. copolyester having a melting point or a softening point of 100 to 160°C, (C) a cationically polymerizing compd. consisting mainly of an epoxy resin, and (D) a photopolymerization initiator which liberates a Lewis acid when irradiated with an ultraviolet ray. Component (B) is used in 0.05 to 20 pts.wt. per 100 pts.wt. of component (A). Component (C) is used in 5 to 50 pts.wt. per 100 pts.wt. in total of components (A) and (B), and component (D) is used in 0.05 to 10 pts.wt. per 100 pts.wt. of component (C).