Provided is a photocurable moisture-proof insulating coating material which places little burden on the environment and has excellent surface curability with low irradiation. In addition, this photocurable moisture-proof insulating coating material is hydrophobic and exhibits high adhesion to a substrate material. Also provided is a novel urethane (meth)acrylate which is used for this moisture-proof insulating coating material. A urethane (meth)acrylate of the present invention is obtained by reacting (a) a polyester polyol that has a structural unit derived from a hydrogenated dimer acid and a structural unit derived from a hydrogenated dimer diol, (b) a polyisocyanate compound and (c) a hydroxyl group-containing (meth)acrylate. A moisture-proof insulating coating material of the present invention contains this urethane (meth)acrylate and a (meth)acryloyl group-containing compound that does not contain a silicon atom.