[Objective] In order to provide a scientific basis for prevention of soil erosion on slope farmlands in mountainous area of Yunnan Province, the effects of reverse-slope level terraces on soil and water conservation and soil carbon stock of slope farmland were studied.[Methods] A comparative experiment was conducted in a fixed 1 year run-off observation plot located in Yizhe watershed of Kunming Songhuaba reservoir under natural rainfall condition. Surface runoff, sediment quantity and the loss of soil organic carbon from slope farmland with and without reverse-slope level terraces(act as control) were measured.[Results] (1) As an important carrier of soil organic carbon, the loss of sediment-bonded soil organic carbon accounted for over 85% of the total organic carbon lost with runoff, and the maximum bonded loss proportion could reach 95.38%.(2) The reverse-slope level terrace performed significant effects on promoting soil and water conservation and on reducing runoff and sediment. The reduction rates of runoff and sediment by the reverse-slope level terrace were 5.56%~53.91% and 18.84%~83.11%, respectively, showing that the sediment reducing effect of reverse-slope level terrace was more prominent than that of carbon reducing effect.(3) The reduction rate of soil carbon storage of slope farmland with reverse-slope level terrace was 3.99% during the rainy season, which was significantly less than that of the control of 9.90% reduction.(4) Correlation analysis by the observations from treatment with reverse-slope level terrace and the control showed that the loss rate of soil organic carbon from slope farmland was not significantly correlated with rainfall, it was significantly correlated with erosion capacity of the rainfall(p<0.05). The runoff and sediment quantities were significantly and positively correlated with the loss rate of soil organic carbon in both of the two observation plots(p<0.05).[Conclusion] Mainly by changing micro-topography of land surface, reverse-slope level terrace had remarkable effect on reducing the output of soil organic carbon from slope farmland.