In response to the problem that the potato picking device installed on a self-propelled potato picking and bagging machine is prone to soil accumulation in the front, resulting in poor transportation of the potato soil mixture. Therefore, the driver needs to frequently manually adjust the depth of the picking shovel into the soil, which can easily lead to misjudgment and result in the failure of the key operation indicators of the whole machine’s potato damage rate, leakage rate, and impurity rate to meet the operation requirements. A potato picking device operation parameter self adjustment system was studied. During the operation of the device, based on the real-time measurement of the height of the soil accumulation by ultrasonic sensors, the depth of the picking shovel entering the soil, the linear speed of the conveying chain, and the vibration intensity of the potato soil separation were continuously adjusted through hydraulic drive to achieve optimal operation quality. Based on DEM-MBD coupling simulation, the simulation was conducted on the operational quality of the picking device under different combinations of operational parameters, clarifying the general law of the impact of operational parameters on operational quality. Based on this law, a self adjustment method for homework parameters was designed. Based on the control requirements of device operation parameters, a simulation of electro-hydraulic control system was conducted by using AMESim-Matlab/Simulink. The control effects of fuzzy PID and classical PID were compared, and the simulation results showed that fuzzy PID control improved the response speed of valve-controlled cylinder system and valve-controlled motor system compared to classical PID control. The field experiment was carried out by using the fuzzy PID control operation parameter self adjustment system on the picking device. The test results showed that the picking device equipped with the operation parameter self adjustment system had a potato leakage rate of 2.17%, a damaged potato rate of 2.51%, and a impurity rate of 1.64% during operation. All indicators met the operational requirements and were superior to manual control, verifying the superiority of the potato picking device equipped with a self adjusting system for operational parameters over manual control.