Polycaprolactone (PCL), a synthetic aliphatic polyester, was buried in activated sludge soil for 66 days at $27^circ{C}$ and $37^circ{C}$. The morphology of the surface of PCL film degraded by soil microorganisms was observed. Soil microorganisms degrading PCL were isolated and identified. Soil fungi and soil bacteria utilizing PCL as carbon or energy source were identified as Paecilomyces fumosoroseus KH27, Penicillium digitatum KH28, Fusarium solani KH29, Aspergillus sp. KH30 and Ochrobactrum anthropi KH31, respectively. Biodegradation test of PCL by the isolated strains showed that, P. digitatum KH28 exhibited the most PCL degrading activity at $27^circ{C}$. However, at $37^circ{C}$ O. anthropi KH31 showed higher degrading activity than the other soil microorganisms tested.