A highly bendable insulated electric wire including: a conducting wire formed by stranding a plurality of metal strands; and an insulator covering the conducting wire, in which a twist pitch ratio of the conducting wire (a twist pitch/an outer diameter of the conducting wire) is 10.8 or less, the insulator is made of a resin composition containing a vinyl chloride resin and having an elongation rate of 130% or higher at −40° C., and an adhesion strength between the conducting wire and the insulator is 20 N or less.