[Background] The terrain features of the rocky mountain area in northern China are characterized by thin soil layer, long steep slope, wave type undulating,mainly soil and water erosion in slope farmland. The soil erosion of this area is serious, and the erosion channels are intensive, causing serious soil and water loss to the local and downstream. [Methods] In order to solve the soil erosion problems of wave type slope farmland, based on the morphological features of wave type slope farmland and its characteristics of soil and water loss, we designed the interception-precipitation-drainage technology on wave type slope, deployed the cells with the technology (measure cell) and contrast cell, and observed the runoff and sand output. [Results] 1) The average rate of cutting flow and rate of erosion reduction on the wave type slope by interception-precipitation-drainage technology in 2 years were 53. 72% and 87. 21%, respectively, meaning that favorable results of both cutting flow and reducing erosion achieved. The technology presented solid cutting runoff effect on slope for all kinds of rainfall, and the drainage system of the measure cell showed feasible reliability and stability. 2) Analyzing the erosion caused by different rainfall intensity, the interception-precipitation-drainage technology on wave type slope played a better effect on the runoff regulation in large rain intensity. Through the trend line analysis, the linear slope between runoff and rainfall of the contrast cell was greater than that of measure cell (trend line close to horizontal level), indicating that the amount of sediment produced by different rainfall was very small under the interception-precipitation-drainage technology on wave type slope, i. e. , the sediment reduction effect of the interception-precipitation- rainage technology on the wave type slope was significant. 3) According to the analysis of the data of individual rainfall, the sediment erosion amount on the measure cell was much smaller than that of the contrast one. The annual sediment erosion on wave type slope farmland was mainly caused by several downpours, the interception-precipitation- drainage technology on wave type slope had significant effect on decreasing erosion under the downpours. Analysis by adding trend line showed that sediment erosion in the measure cell had no good linear relationship with rainfall, rainfall intensity and I30, and the sediment erosion on the measure cell was influenced jointly by rainfall, rainfall intensity and I30. Moreover, in the rainy season, the sediment erosion on the measure cell was largely affected by surface roughness. 4)Regarding the crop yield, on the same condition of fertilization, the increasing production effect of the wave type slope interception- precipitation-drainage technology was more obvious in dry year than flat water year. [Conclusions] Therefore, the interception-precipitation-drainage technology on the wave type slope may effectively prevent the soil and water loss on wave type slope farmland, which can be used as a novel control technology of soil erosion on slope farmland.