Abstract: Abstract: 4HLB-4 type semi-feeding four-row peanut combine harvester gets 2 ridges (4 rows) at one time, whose productive efficiency is 2 times more than the existing semi-feeding two-row peanut combine harvester. Bar strip screen, woven screen and perforated screen and other traditional screens are widely used in semi-feeding peanut combine harvesting, but in practice, it is found that the traditional screens can not meet the demand of changeable soil moisture content and the requirement of high efficiency. In the application of semi-feeding four-row peanut combine harvester, there are many problems such as high percentages of impurities and loss, and debris blockage. In order to overcome the above difficulties, a stacked elastic steel pole oscillating screen was designed in this paper, and it can transfer dynamic load to the elastic steel pole to motivate elastic vibration of itself, which has a very good breaking and flipping effect on the mixture of peanut and varia on the screen surface and is good for screening operation and improves screening quality and speed effectively. In this paper, the percentages of impurities and loss were taken as the evaluation indices, and the contrast tests for 3 kinds of traditional screens (bar strip screen, woven screen and perforated screen) and elastic steel pole oscillating screen were carried out when the operating speed was 0.8, 1.0 and 1.2 m/s respectively. The test results showed that cleaning effect of elastic steel pole oscillating screen was better than the other 3 traditional screens in 3 operation speeds. Based on the single factor experiment, vibration frequency of elastic pole screen, diameter of elastic pole, altitude of elastic pole screen, mounting angle were selected as influencing factors. The four-factor three-level quadratic regression orthogonal test was carried out by using Box-Benhnken central composite test method. Two polynomial regression models about percentage of impurities and percentage of loss v.s. the 4 variables including vibration frequency of elastic pole screen, diameter of elastic pole, altitude of elastic pole screen, and mounting angle were established. Response surface methodology was used to analyze the influence of various factors on percentages of impurities and loss, and the influence factors were optimized. The experimental results showed that different factors and their interactions had different influence on the measured indices. The significant sequence for percentage of impurities was vibration frequency of elastic pole screen > diameter of elastic pole > altitude of elastic pole screen > mounting angle. The significant sequence for percentage of loss was altitude of elastic pole screen > mounting angle > vibration frequency of elastic pole screen > diameter of elastic pole. In order to find the best combination of parameters, the minimum percentages of impurities and loss were taken as optimization targets, a research on parameter optimization of the screen was carried out, and the constraint condition of objective function and parameter variable was established. The optimal parameter combination of vibration frequency of elastic pole screen of 6 Hz, diameter of elastic pole of 3 mm, altitude of elastic pole screen of 7 mm and mounting angle of 2.8° was obtained using optimization module of Design-Expert data analysis software. Field experiments were carried out with the above optimized parameters, and the percentage of impurities was 2.41% and the percentage of loss was 0.711%. The relative errors of each evaluation index and its theoretical optimization value were less than 5%. The research results can provide references for the perfect design and operation parameter optimization of 4HLB-4 type semi-feeding four-row peanut combine harvester and cleaning component.