Abstract: In recent years, with the increase in the area of domestic sunflower planting, with the supporting mechanised production system is relatively backward, especially the low level of mechanised harvesting. Currently, the harvesting of edible sunflowers in China mainly adopts segmented harvesting, first cutting the sunflower disc and then inserting it on the sunflower stem to dry for about 7-10 days. After the moisture content of seeds meets the harvesting conditions, mechanical harvesting is used, which is time-consuming, labor-intensive, and causes significant losses, that the serious constraints on the development of the sunflower industry have led to limited reports on the combined harvesting of sunflowers. Therefore, there is an urgent need for mechanized combined harvesting of sunflowers. Due to the thin and short skin of sunflower seeds, while the traditional combine harvester has a long material transportation path after harvesting,thus during the transportation process, the sunflower disc is prone to breakage and the seed skin is easily damaged, leading its economic value greatly reduce, In addition, the severe breakage of the sunflower disc increases the difficulty of subsequent cleaning.Therefore, this study focuses on the problems existing in the mechanized harvesting process of sunflowers mentioned above. Combining the characteristics of sunflowers as high stem crops and easy threshing during the complete maturity stage, this 4KHZ-330 sunflower combine harvester was innovatively designed on the basis of the traditional material process flow of the combine harvester. It achieves the separation of sunflower seeds and impurities on the header, aiming to shorten the transportation path of sunflower discs after harvesting, reduce transportation losses, and reduce sunflower disc breakage. To lay the foundation for improving the cleaning quality follow up,the key component structures and parameters such as cutting threshing integrated type header, cleaning device, and pneumatic conveying device were been designed, and conduct field experiments was conducted to verify the rationality of the design. This article elaborates on the overall design scheme and power transmission mode of combine harvester, and designs key components such as cutting threshing integrated type header, header lifting mechanism, cleaning device, and pneumatic conveying device, and determines their relevant parameters. The machine was equipped with power of 113 kW and working width of 3300 mm,which can complete the cutting, threshing, conveying, cleaning, seed collection, grass collection, and unloading processes of sunflowers. Field experiments were conducted have shown that under three different working gears of low, medium, and high, the total loss rate of the harvester was less than 4.0%, the impurity content of the seeds was less than 5.0%, the damage rate of the seeds was less than 2.0%, and the productivity was 0.40-0.85 hm²/h. The work performance indicators meet the requirements for harvesting sunflowers and are superior to relevant standards. During the work process, the coordination relationship between key components of harvester was stable, the sunflower feeding was smooth, effectively saving manual labor, reducing production costs, and improving work efficiency.This can provide technical reference for the development of subsequent sunflower harvesting equipment.