To provide an optical information medium having a light transmission layer having small film thickness change and excellent dimensional stability to external environmental change (temperature and humidity).

In the optical information medium having an information recording surface on a supporting base body and the light transmission layer on the information recording surface and used so that at least one of recording light and reproducing light is made incident through the light transmission layer, the light transmission layer is a cured product of a curable composition containing a urethane (meth)acrylate (A), a di(meth)acrylate (B) represented by general formula (I), a di(meth)acrylate (C) represented by general formula (II) and a photopolymerization initiator (D) and the cured product has ≥90% reaction ratio and 100 to 600 MPa tensile modulus of elasticity at 23°C.