An adamantane derivative capable of affording a cured product which is excellent in optical characteristics such as transparency and light resistance, durability such as long-term heat resistance, and electrical characteristics such as dielectric constant, a process for producing such an adamantane derivative, and a curable composition containing such an adamantane derivative, the adamantane derivative being represented by the general formula (I) shown below and having a group selected from an acrylate group, a methacrylate group and a trifluoromethacrylate group, where R1 represents a group selected from a hydroxyl group, an acrylate group, a methacrylate group and a trifluoromethacrylate group, R2 represents a group selected from a hydrogen atom, a methyl group and a trifluoromethyl group, k is an integer of 0 to 4 and n is an integer of 1 to 6.