Abstract: Aiming at the problems of heavy labor intensity and high cost in the manual harvest of Xinjiang edible sunflower heads on stalks, a machine for edible sunflower heads on stalks in-situ harvesting was designed, which was composed of in-situ threshing device and seeds recovery device. The edible sunflower stalk entered the in-situ threshing device through the nearside divider, and the stalk was guided to the roller with a strike mode by the chain and the supporting plate, and the roller with a strike mode strike the edible sunflower head to make the seeds fall off. Then the threshing brush removed the seeds at high sipping speed. After threshing, the seeds fall into the collecting hopper. Finally, the seeds were drawn into the sealed collection box by the conveying air duct. And the threshing and collection of seeds were completed. Based on the analysis of statics and kinematics theory, the in-situ threshing device of combined strike-brush was designed, and the main factors affecting the threshing effect of edible sunflower were determined. Combined with the characteristics of edible sunflower seeds, the structural parameters of the air-suction seeds recovery device were preliminarily determined. The method of discrete element and fluid coupling analysis was used to simulate the seeds recovery device, and the operation process of collecting hopper and sealed collection box was simulated and the operation parameters of the fan satisfying the seeds collection performance were obtained. Through the single factor experiment, the reasonable range of the speed of the machine, the threshing brush and the roller with a strike mode was determined. Based on the single factor experiment results, the orthogonal experiment was carried out on the whole machine with speed of the machine, threshing brush and a strike mode as test factors, and the un-threshing rate of edible sunflower head and damage rate of seeds as evaluation indexes. The experiment results showed that when the speed of the machine was 0.3 m/s, the speed of the threshing brush was 130 r/min, and the speed of the roller with a strike mode was 80 r/min, the working performance of the machine was the best, and the un-threshing rate of the edible sunflower head and the damage rate of the seeds were 7.11% and 1.13%, respectively. The research results can provide reference for the design of edible sunflower harvesting machinery.