Abstract: This paper studied the activities of superoxide dismutase (SOD)and peroxidase (POD) a-mong roots, shoots and leaves in Chinese fir seedlings, The most activities of SOD,POD existed in leaves of Chineses fir. Under drought stress Chinese fir family 39 showed less electrolytic leakage and higher SOD, POD activities. Under low temperature the outward of seedlings appeared injure symptoms , the cells in leaves occurend large amounts of electrolytic leakage, the SOD, POD activities reduced siginificantly. The difference of which existed in various families, the cells in leaves of No. 6421 showed less electrolytic leakage, and large SOD, POD activities, The results indicated the different resistance existed in various Chinese fir families.