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Effects of tillage on soil carbon and nitrogen retention and stratification in ricewheat system were studied to provide a theoretical basis for exploring tillage methods which could be beneficial to the construction of soil organic carbon (SOC) and total nitrogen (TN) pools and the improvement of soil fertility in farmland. A fouryear field experiment was conducted based on Heheng demonstration park of ecoagricultural science and technology, including four treatments of minimum tillage with straw retention (MT), rotary tillage with straw retention (RT), conventional tillage with straw retention (CT) and conventional tillage without straw retention (CT0). Soil at 0~20cm depth was collected to determine soil bulk density, content of SOC and TN. Then the ratio of C to N, the stratification ratio and the SOC and TN storage (using the equivalent soil mass approach) were calculated. Results showed that the contents of SOC and TN in 0~5cm, 5~10 and 10~20cm depths were increased by MT, RT and CT, respectively. Soil C∶N ratio at 10~20cm depth was decreased with the increase of tillage intensity. MT significantly increased the stratification ratio of SOC and TN, while the stratification ratio of C∶N ratio at 0~5cm and 10~20cm depths was increased with the increase of tillage intensity. MT increased the SOC stocks at 0~20cm depth and the TN stocks at 0~10cm depth, but the TN stocks at 0~20cm depth were lower than those of RT and CT. Straw retention significantly increased SOC and TN contents and C∶N ratio, which were beneficial to SOC and TN sequestration, but it had no significant effect on stratification ratio of SOC and TN contents at 0~20cm depth.