To provide a urethane oligomer without an organic solvent, hardly skin-irritative, which can be used as a curing component for an adhesive agent for medical purpose requiring good adhesion to skin and destroying no keratin of skin and for medicines/garment fibers requiring moisture permeability.

This urethane oligomer is represented by the formula: A-I-[(-P-I-)r-(-B-I-)s]t-M; where A- is a dehydrogenated residue of hydroxyalkyl(meth)acrylate; -I- is an organic-diisocyanate-derived dicarbamoyl group; -P- is a dehydrogenated residue of a polypropylene grycol having a number average molecular weight of 500-5,000; -B- is a dehydrogenated residue of a polyol having a carboxy group; -M is a dehydrogenated residue of a monool; r is an integer of 1-20 and s is 0-20 when t=1; and r and s are each 0-1 at both terminals of the repeating unit (P-I-)r-(B-I-)s and r and s are each 1-15 at positions other than terminals when t=2-15.