It is difficult to guarantee the stability of soil compaction system under the condition of high speed no-tillage seeding. Therefore, a technical scheme of automatic soil compaction control was proposed, and the electro-hydraulic control system for soil compaction of maize planter was designed. The overall structure of the system was proposed, and the pressure control process was determined through the mechanical analysis of the movement of the seeding monomer and the interaction between suppression wheel and soil. The electro-hydraulic control system design and hardware selection were carried out. AMEsim simulation analysis and step response test were used respectively to design the hydraulic actuator and electronic control system. The results showed that compared with the traditional mechanical regulation, the adjustment accuracy and stability of the hydraulic actuator using PID control were improved. The mean adjustment time of the control system for soil compaction was 1.9s, the mean steady-state error was 1.9N, and the mean overshoot was 2.0%. It was obviously better than mechanical control. Sinusoidal surface soil trough verification test was adopted, and comparative experimental study was carried out on the influence of different adjustment methods and surface conditions on the stability of soil compaction. The results showed that when the target pressure was 300N, the RMSE of the pressure using electro-hydraulic control was 30.1% lower on average and the variation coefficient of soil compaction was 24.46 percentage points lower than that by using traditional mechanical control. When the maximum surface displacement in the vertical direction of sine curve was 0mm, 20mm and 40mm, respectively, the variation of RMSE was not significant with the increase of the target force, and the maximum difference was 39.2N. The automatic soil compaction control system of maize planter based on electro-hydraulic control can guarantee the compaction operation quality under different work conditions. It provided technical and equipment support for the construction of seed bed and maize sowing under the condition of high speed and no tillage in arid region.