To clarify the influences of tillage and weeding and slope length on the losses of nitrogen (N) and phosphorous (P) under natural rainfall in purple soil area,9 plots combined with two land disturbances (tillage and weeding and natural restoration) and three slope lengths (20,40,and 60 m) were established to compare the runoff and sediment yield,and N and P losses. The results showed that slope length had no remarkable effect on the runoff and sediment yield under the same land condition (P>0.05),while tillage and weeding plots significantly differed the runoff and sediment yield from natural-restored plots under the same slope length (P<0.01). Natural-restored plots of 20,40,60 m respectively reduced runoff by 77.55%,62.62%,79.56%,and sediment yield by 85.21%,94.97%,96.25%,compared with the tillage and weeding plots. There were significant effects of land disturbance on runoff-related DN and DP losses under 20 and 60 m plots (P<0.05) and on sediment-related TN and TP losses across all plot lengths (P<0.01). Natural-restored plots could reduce the losses of DN and DP in runoff by 75.13% and 80.22%,and the losses of TN and TP in sediment by 96.07% and 96.38%,respectively. Rainfall intensity had significantly power relationship with runoff and sediment yield,and TN and TP losses with sediment-related under tillage and weeding plots,but there was no significant relationship under natural-restored plots. The results can provide theoretical reference for N and P losses and non-point source pollution control in the purple soil area.