Aiming at the problems of the unreasonable working width and straw throwing distance of the row cleaners and poor stability of the working width of notillage planter when working in the field, an automatic width control row cleaner was designed. A mathematical model of the row cleaning width was established, the main operating parameters that affected the row cleaning and the missing cleaning area were determined, and the value range of each parameter was obtained. An automatic width control system was designed by using S-type pressure sensor and electric linear actuator. The method of combining orthogonal experiment design and EDEM discrete element simulation technology was adopted, and the optimal working parameter combination of the row cleaners was determined, and the operation performance of the automatic control system and the row cleaners were verified by field experiments. The research results showed that the main working parameters that affected the working width and the missing cleaning area of the row cleaners were the distance of the two cleaners, the working deflection and the working inclination angle. The optimal combination of parameters obtained by the simulation test was that the distance of the two cleaners was 90mm, the working deflection angle was 30° and the working inclination angle was 15°. The automatic control system monitored the pressure of the row cleaners on the soil and adjusted its depth into the soil in real time, thereby regulating the operation width of the row cleaners, which can effectively improve the stability of the width by 8.7 percentage points. Field test results showed that the straw cleaning rate, straw lateral movement distance and width stability of the device were 92.3%, 40.2mm and 92.1%, respectively, which can meet the agronomic and technical requirements of no-tillage planting operations. The research results can provide reference for the design of similar soil contact parts.