An artificial rainfall simulation experiment was conducted at the intensity of 90 mm/h,under different straw lengths and different straw coverage to study the characteristics of runoff and sediment production on the slope and the regularity of runoff and sediment production process. In order to quantify the effects of different wheat straw lengths and mulches on the characteristics and process mechanisms of slope runoff and sediment yield,as well as the benefits of water and sediment reduction efficiency under different straw conditions. Results showed that: (1) Under the same straw length,with the increase of straw coverage,the yield and sediment yield decreased significantly (p<0.01). At the same coverage level,with the increase of straw length,the yield increased significantly (p<0.05),and the yield of sand increased significantly under the coverage of 4.5 t / hm² (p<0.01). (2) The initial runoff time of the straw-covered slope surface was 6.23 times longer than that of the bare slope surface,and the average production flow rate decreased by 19.5%,the sediment yield decreased by 31.6%. Covering measures effectively inhibited the trend of trench erosion to cut trench erosion by protecting the structure of the soil. The process of runoff and sediment production is affected by the interaction of straw length and mulch. The effect is more prominent on the process of runoff. (3) With the increase of coverage,the benefits of water and sediment reduction increased significantly (p<0.01); with the increase of length,the benefits of water and sediment reduction decreased to 17.26% and 27.97% respectively. The slope runoff yield,sediment yield,water reduction,and sand reduction benefits under the different covering conditions have a binary linear relationship with straw length and straw coverage. (4) Under the experimental conditions,when the straw length is 3 ~ 5 cm,with the amount of 4.5 t/hm²,the optimal water and sediment reduction benefits are achieved.