A field experiment that started the winter of 2008 was carried out to study the effect of Chinese milk vetch in winter on rice yield and its nutrient uptake under the condition of different inorganic fertilizer application rate.The results indicated that the rice yield and total N uptake of rice shoot increased after Chinese milk vetch grown under the same fertilization.The yield of rice and straw did not decrease when chemical nitrogen fertilizer reduced 20%~40% after ploughing the Chinese milk vetch back.The rice shoot of treatment which application the chemical N,P,K fertilizer 100% after ploughing the Chinese milk vetch back had the highest absorption about total N,total P and total K，and the total absorption were 2286，486 and 3056 kg/hm2 respectively.When nitrogen decreased by 20%，the nitrogen uptake of rice shoot had no significant effect.But when nitrogen decreased by 40%，the effect of the nitrogen uptake of rice shoot was significantly.The rice yield of no potassium application after ploughing the Chinese milk vetch back was decreased by 130% and 34% compared with the treatments of NPK(grew Chinese milk vetch in winter) and NPK(fallow in winter) respectively.Because of no potassium application，the total absorption of nitrogen and potassium of rice shoot decreased significantly，the physiological efficiency of potassium was increased.Therefore the Chinese milk vetch was planted in winter could not substitute the role of chemical potassium fertilizer completely.