Sheet flow runoff on loess hillslope was studied through simulated rainfall experiments, under the conditions of rainfall intensities of 1.00，1.33，1.67，2.00，2.33 mm min^-1 and slopes of 9°，12°，15°，18°，21°.Results show that 1) regardless of rain intensity and slope degree, the runoffs displayed a general trend in rate, that is, increasing first and leveling off late, however, the turning point came 5 min earlier in treatments of rain intensity than in treatments of slope degree, and the variation could be described with a logarithm equationy=aLn(x)+b; 2) depth of the sheet flow runoff varied with rainfall intensity and slope gradient as well, which could be described with a power function equation H=aI^band H=aS^brespectively; 3)the integrated response of the runoffs in depth to rainfall intensity and slope gradient could be described with a dual power function equation H=3.83I^1.01S^0.490, and the response to rainfall intensity was greater than to slope gradient; and 4)the effect of sheet flow runoffs on sheet erosion was significant, and varied with rainfall intensity and slope gradient, which could be described with a power function equation M= 0.0378 H^1.21and a linear equation M = 0.235 H -3.48 respectively.