[Objective] The effects of conservation tillage on crop yield and soil erosion in sloping land of yellow soil were analyzed in order to provide scientific basis for soil and water loss control an agricultural sustainable development in Guizhou Province.[Methods] In the typical slopping land of yellow soil in southwest China, nitrogen and phosphorus loss, surface runoff and soil nutrient content were investigated under different tillage systems from 2017 to 2018. Six monitoring plots were set up, including no fertilization + downslope conventional tillage(TR₁), conventional fertilization + downslope conventional tillage(TR₂), optimized fertilization+downslope conventional tillage(TR₃), optimized fertilization +cross ridge tillage(TR₄), optimized fertilization +cross ridge tillage + straw mulching(TR₅), optimized fertilization + cross ridge tillage + straw mulching + contour hedgerow(TR₆).[Results] ① Compared with TR₃, the runoff of TR₄, TR₅, TR₆ were reduced by 59.72%, 74.13% and 89.18% respectively, and the total loss of nitrogen and phosphorus showed a same varying trend. ② TR₅ and TR₆ had the greatest impact on total nutrient content, of which total nitrogen was 20.00% and 23.67% higher than TR₄, 23.53% and 27.31% higher than TR₃, respectively. ③ Maize yield stability(SI) and sustainability(SYI) were the best with TR₄, TR₅ and TR₆ treatments while maintaining a high yield. ④ The yield of maize and rape was significantly and positively correlated with total nitrogen, total phosphorus, available phosphorus and organic matter(p<0.01), and positively correlated with available nitrogen(p<0.05), while negatively correlated with nitrogen loss, phosphorus loss and runoff(p<0.01).[Conclusion] Conservation tillage in sloping land could effectively reduce surface runoff, the loss of nitrogen and phosphorus, maintain the soil nutrient fertility and promote high yield of crops, and achieve a stable and sustainable production, and the effect of comprehensive conservation tillage measure is greater than that of single conservation tillage measure.