Abstract: To clarify the effect of oilseed rape straw returning on the growth of rice roots and tillers by different incorporation methods,and to provide theoretical basis for the utilization of agricultural sources and the sustainable production of oilseed rape-rice rotation system,a split-plot field experiment was carried out at Longmen,Sichuan Province.The results showed that the amount of oilseed rape straws and the days after transplanting both affected the growth of rice roots and tiller significantly,and the amount of oilseed rape straws was negatively related with the growth of rice.Meanwhile,rice roots and tillers grew slowly during the early stage (0—19 days after transplanting),while showing a rapid growth during the late stage (more than 19 days after transplanting).The highest growth rate was found when 1.5 t/hm2 oilseed rape straw was returned.24 days after transplanting,there was a minimum growth rate at (61.11%,74.80%,317.91% and 140.35% ) with treatment M0,M0.5,M1.0 and M1.5,respectively,which was similar with the maximum growth rate ( 105.6%,119.7%,335.8%,118.6%) by treatment G0,G0.5,G1.0 and G1.5,respectively.It was concluded that the incorporation of oilseed rape straws inhibited the growth of rice roots and tillers during 0—15 days after transplanting.The growth was more inhibited by plough than the straw mulching method.However,straw returning by plough is better to the growth of rice roots during the late stage.The straw returning amount of 1.5 t/hm2 is the most conducive to the growth of rice roots and tillers either by plough or mulching.