The present invention provides a novel polycarbonate diol and a polyurethane using the polycarbonate diol as raw materials. The novel polycarbonate diol produces polycarbonate diol-based polyurethane which has a high degree of hardness, superior abrasion resistance, and superior hydrophilicity, and is usable for an application such as a paint, a coating agent, a synthetic leather, an artificial leather, and a highly-functional elastomers, or the like. The present invention also provides an active-energy radiation curable polymer composition giving a cured film having a superior contamination resistance and high degree of hardness. The present invention is obtained, for example, by reacting specific two types of diols with diester carbonate in the presence of a transesterification catalyst being a compound using a metal of Group 1 or 2 on the periodic table. The present invention provides a polycarbonate diol wherein the metal content of the transesterification catalyst is 100 weight ppm or less, a polyurethane obtainable by using this polycarbonate diol and an active-energy radiation curable polymer composition containing the urethane(meth)acrylate oligomer which is obtained from the polycarbonate diol.