Slope soil is an important soil resources in the subtropical region of China where there is a relatively serious soil erosion caused by unreasonable utilization and heavy rainfall.Nitrogen and phosphorus losses in runoff,nutrient accumulation in southern purple slope soil(slope=15°)were monitored in field.Three treatments were set up,including longitudinal ridge(CK),cross ridge(KF)and cross ridge with straw mulching(BMP).The results indicated that runoff amount and nitrogen and phosphorus losses in runoff of the three treatments in May were very high,which accounted for more than 40% of the loss of the whole year.The mean and maximum values of nitrogen and phosphorous concentration over the whole year were all decreased in KF and BMP treatments compared to the CK treatment.In tobacco growing season,nitrogen concentration in runoff of CK，KF and BMP were 3.44,3.37 and 3.28 mg·L-1,respectively; in sweet potato growing season,their values were 2.79,2.61 and 2.63 mg·L-1; in fallow season,their values were 3.01，2.78 and 2.64 mg·L-1.The runoff losses of CK，KF and BMP were 5 553,5 347 and 2 905 m3·hm-2,respectively,and the difference between CK and BMP was significant.The differences of runoff,total nitrogen(TN),NO-3N,NH+4N,total phosphorous(TP)and total dissolved phosphorous(TDP)losses in runoff between CK and BMP treatments were all significant(P<0.05),but the these differences between KF and CK were not significant although the values were all decreased.At the mean time,BMP treatment increased the minimum precipitation value when the runoff could occur.The results indicated that the effect of cross ridge measure on nutrients loss derived from runoff was limited,while cross ridge with straw mulching significantly decreased runoff and nutrients loss in steep hillslope soil.