A copolycarbonate having a high refractive index, a small birefringence, high processability and excellent transparency and an optical lens formed from the copolycarbonate.The copolycarbonate has a total content of a unit represented by the following formula (I) and a unit represented by the following formula (II) of not less than 80 mol % based on the total of all the recurring units, the molar ratio of the unit represented by the formula (I) to the unit represented by the formula (II) being in the range of 98:2 to 35:65. (wherein each of R1, R2, R3 and R4 is independently a hydrogen atom, alkyl group having 1 to 20 carbon atoms or the like. X is an alkylene group having 2 to 8 carbon atoms or the like. Each of m and n is independently an integer of 1 to 10.) (wherein each of R5, R6, R7 and R8 is independently a hydrogen atom, alkyl group having 1 to 20 carbon atoms or the like.)