Biodegradable epoxy thermosets were developed by curing through copolymerization of a diglycidate monomer, a bifunctional epoxide bearing ester linkages, with cyclic acid anhydrides as a biosafe thermosetting system. The cured products of the glycidate exhibit high adhesiveness, identical to analogous cured products of conventional glycidyl ethers. Even an inert cycloolefin polymer and polyimide can be adhered. The cured products of the glycidate can be hydrolytically and biologically degraded. The biodegradation of the glycidate thermoset in compost completely proceeded within 2 weeks.