Abstract: The comparative experiments were conducted to study the effect of different tillage methods in root activities and yield characters. The results showed that the root activity of rice plants in the no-tillage treatment increased by 7.4%~34.9%, the ratio of dry-matter in different stages to that of yellow maturity stage was bigger, the effective spikes, filled grains per spike, 1000-grain weight and actual yield were increased separately by 1.1%, 5.1%, 0.6% and 10% than early rice cultivated in conventional paddy. The correlation coefficient between the activity of root system of early rice, dry-matter and the yield were bigger individually than 0.9 and 0.87.