In this paper, the efficiency of controlling rice pests, diseases and weeds by releasing ducks in paddy fields was investigated. The results showed that populations of planthopper and leafhopper were decreased by 63.8% and 77.3%, respectively in 12d and 42d after releasing ducks, and the weeds were decreased by 50.6% and 94.2%, respectively in 10d and 40d after releasing ducks when compared with the check plot with no ducks. The sheath blight index in active tillering stage and heading stage in the duck growing rice plots were 67.1% and 52.5% less than those in the check, respectively. The population of spiders in the duck released field was increased by 1.66-2.61 times than that in the conventional rice field