Susceptibility of an aliphatic polycarbonate, poly(tetramethylene carbonate) (PTC) to various preparations of lipolytic enzymes was examined. PTC was degraded by a cholesterol esterase (CE, EC 3.1.1.13) preparation from Candida cylindracea, lipoprotein lipase (LPL; EC 3.1.1.34) preparations from Pseudomonas sp., and lipase (EC 3.1.1.3) preparations from C. cylindracea, Chromobacterium viscosum, porcine pancreas, Pseudomonas sp., and Rhizopus arrhizus. Particularly strong activities were detected in the preparations of lipase and LPL from Pseudomonas sp. The degradation reaction of high molecular weight PTC was further examined using the preparation of LPL from Pseudomonas sp. PTC oligomers appeared first with the disappearance of substrate substrate PTC polymer. The PTC oligomers were further degraded into smaller units. The evolution of CO2 was detected at the same time. After 48 h of incubation, the PTC polymer was almost completely degraded and the final products were 1,4-butanediol, CO2, and one mole water soluble component which was identified as a diester, di(4-hydroxybutyl) carbonate.