Abstract: In order to explore the influence of different straw returning modes on carbon footprint in a rice-wheat rotation system, a 2-year field experiment was carried out. In this study, three wheat straw returning modes were set up (wheat straw retuning with rotary tillage, wheat straw retuning with plowing, and wheat straw ditch-buried returning) with no straw returning as the control. The static chamber-gas chromatography method was used to measure greenhouse gases emission and other carbon emissions were calculated by analyzing emissions from the production of main goods and the associated processes during the life-cycle period of rice-wheat rotation. The results indicated that compared with no straw returning, the wheat straw returning significantly increased the average daily CH4 emission and the annual CH4 emission in the rice field accounted for 95% of the global warming potential. In the rice season, the CH4 emission explained the most share of carbon footprint and the wheat straw ditch-buried returning showed the lowest amount among those three wheat straw returning treatments, which was 4.9% lower than that under wheat straw retuning with rotary tillage. In wheat season, carbon footprint derived from chemical fertilizer input was the largest, accounting for 64.5%~77.4%, followed by N2O emission. For the whole rice-wheat rotation, both carbon footprint and yield-scaled carbon footprint under wheat straw ditch-buried returning were the lowest among the straw returning treatments, which was 4.6% and 3.6% lower than wheat straw retuning with rotary tillage, and 8.7% and 4.9% lower than that with plowing. Thus, wheat straw ditch-buried returning might be an effective way to reduce agricultural carbon emission in rice-wheat rotation system.