Abstract: Pot experiments were conducted in the early and late seasons of 2007 to compare the differences of activities of antioxidant enzymes in rice root under no tillage, conventional tillage and root separating cultivation conditions. Results showed that activities of SOD, CAT and POD in the root of no tillage rice or no tillage side in separating cultivation were lower that in root of conventional rice root or in root of conventional side in separating cultivation at elongation stage, while their contents of MDA were higher. However, this trend was exactly opposite. It can be concluded that, compared with conventional tillage rice, no tillage rice was provided with the characteristic of slower root senescence at later growth period.