Abstract: A novel copolycarbonate is provided, which comprises recurring units respectively of the formulae: ##STR1## in a molar ratio of units (A) to units (B) of from 9:1 to 1:9. The copolycarbonate has a number average molecular weight of from 300 to 50,000. The copolycarbonate is useful as a reactive polymer for producing final polymers such as a polyurethane and a thermoplastic elastomer. The copolycarbonate as well as various final polymers produced therefrom have excellent resistance to hydrolysis, light, chlorine, oxidative degradation, heat, etc. The polyurethane and the thermoplastic elastomer containing units of the novel copolycarbonate as soft segments exhibit remarkably improved flexibility and elastic recovery as compared to those of the conventional polymers.