Xanthoceras sorbifolia is a kind of woody oil-bearing plant endemic to China.However,its fruit-setting rate is very low,and there is a common saying like this: one thousand of flowers,but only one fruit.Two factors,water and NAA,were selected to study their effects on the fruit-setting rate.There are two experiments.One is only controlling the watering times during the full-bloom stage.The other is controlling the watering times together with 50ppm NAA application during the full-bloom stage.The results suggested that watering in the full-bloom stage led to a large number of flowers and fruits dropped,the fruit-setting rate only reached 1.98%-2.56%.Whereas if no watering but spraying 50ppm NAA in the full-bloom stage could improve the fruit-setting rate and prevent the flowers and fruits dropping significantly and effectively.The fruit-setting rate reached 88.57%-92.68%.