Abstract: A three-year experiment was conducted to study the responses of single cropping rice's growth to different period and ratio of reducing nitrogen (N) and potash (K) application after turning Astragalus sinicus green manure to filed. The results showed that,after turning Astragalus sinicus 18000 kg穐m-2 into field every year, the yield of rice grain was the highest in N and K fertilizer treatment with base fertilizer:tillers fertilizer:panicle fertilizer=0:5:5, and respectively increased by 3.6%, 4.9%, 3.0% and 6.1% than that of treatments with base fertilizer:tillers fertilizer:panicle fertilizer=3:4:3, 5:5:0, 0:7:3 and 0:10:0, and the differences showed significant. The main economic characters which improved the rice yield was the increase of the setting grains per panicle. This may be the enough nutrient offered to single cropping rice in seeding stage after turning Astragalus sinicus manure into field. N and K fertilization application in retral growing period and the increase of panicle fertilization ratio could significantly improve the yield of rice grain.