In order to explore the aftereffects of applying biochar in the double-season rice fields in southern China，this study compared and analyzed the effects of new biochar application(application rates are 0，20 and 40 t·hm-2，expressed as B0，B20 and B40)and biochar application two years ahead(the application rate is the same as B20 and B40，respectively expressed as Y2B20 and Y2B40)on the growth of double-season rice and the physical and chemical properties of the soil，with a view to providing theoretical and scientific basis for the rational application of biochar.The results showed that biochar and its after effect significantly increased pH，the content of soil organic carbon and available potassium，and the effect of newly applied biochar was higher than that of biochar applied 2 years in advance.Compared with B0，the new application of biochar significantly increased the yield of early and late rice and aboveground biomass.The yields of B20 and B40 early rice were significantly increased by 6.9% and 12.6% respectively，and the yield of late rice was significantly increased by 9.4% and 8.3% respectively；for Y2B20 and Y2B40，compared with B0，the yield of early rice decreased significantly by 3.4% and 4.6%，respectively，and had no significant effect on the yield of late rice.In the newly applied biochar treatment，the nitrogen and phosphorus contents in the stems and leaves of early rice and late rice were significantly reduced，while the potassium content showed a significant upward trend with the increase of biochar application.The application of biochar treatment two years ahead had no significant effect on the absorption of nitrogen and phosphorus in early rice and late rice.Only Y2B40 significantly increased the absorption of potassium in late rice.The absorption of nitrogen，phosphorus and potassium in the newly applied biochar showed an upward trend with the increase of biochar application.Compared with B0，nitrogen absorption of B40 late rice increased significantly by 9.9%，phosphorus absorption of B20 and B40 early rice increased significantly by 9.9% and 9.1%，respectively，and phosphorus absorption of B40 late rice increased significantly by 9.1%；the absorption amount of potassium of B20 and B40 early rice increased significantly by 22.8% and 39.9%，respectively，and the late rice increased significantly by 9.9% and 19.5%.In summary，there is an aftereffect of the application of straw biochar on the yield，aboveground biomass，nutrient absorption of double-season rice and soil physical and chemical properties，but its aftereffect is shorter，and appropriate supplementation of biochar should be considered.