Abstract: A prelimipary study Was made on the chemical composition of throughfall and its contribution to the nutrient recycling in rice field ecosystem at the late growth stages ( from booting to ripening stage )of hy-brid rice ( Xianyou no. 6 ) . The results showed that the chemical composition of precipitation remarkably changed when it passed through the rice canopy, the concentrationsm of N, P, K, Ca, Mg and Si Were increased.Peak concentrations of these elements occured in milky stage of rice growth.The amount of N, P, K, Ca, Mg and Si recycled by throughfall were 15.91, 1.11, 3-70, 1.13, 1.70 and 8.25 kg/ha respectively.It appeared that the nutrients (especially N)returned to soil by throughfall may be an important mechanism of nutrient recycling in rice field ecosystems.