The full-feed tangential flow type peanut picking operation as the main way of peanut mechanization harvest has problems on short effective time and high loss rate of pod-picking. In order to solve this problem, a multistage tangential flow peanut picker and conveying device was developed which mainly composed of multistage pod-picking cylinder, front conveying plate, vibration drive shaft and rear conveying plate. The conveying device and the pod-picking device of traditional peanut combine harvester were integrated. The mechanism of seven-stage roller in series combined with vibration conveying was proposed to realize synchronous operation of pod-picking and conveying. The structure and parameters of the key components were designed on the basis of the operating principle analysis. The simulation and optimization method of discrete element software EDEM was used to analyze the motion parameters (direction angle, amplitude, frequency) of the conveying board. Taking the typical peanut variety “Dabaisha” in the main producing area as the research object, the simulation results were verified by field experiments in Zhumadian City, Henan Province. The results showed that when the feeding amount of peanut plants, the rotation speed of the second pod-picking cylinder, the rotation speed of the other six pod-picking cylinders, the direction angle of the conveying plate, the amplitude and the frequency were set to be 5.6kg/s, 325r/min, 239r/min, 25°, 45mm and 7Hz respectively, the picking rate, breakage rate and enrolling loss rate of peanut were 98.41%, 4.76% and 1.46%, respectively. The research results were helpful for the development and promotion of mechanized peanut harvesting technology.