The microwave (MW)-assisted lipase-catalyzed ring-opening polymerization of epsilon-caprolactone in boiling solvents was investigated for the first time. In case of boiling toluene or benzene the MW-assisted reaction proceeded significantly slower compared to oil bath heating. On the other hand, using boiling diethyl ether as solvent, an increase of the polymerization rate due to MW irradiation was found. Yield, molecular weight measurements, and MALDI-TOF analysis supported the results.