Abstract: Abstract: Potato is one of the dominant crops in the rain-fed agriculture area of the Loess Plateau in the northwest. To inhibit evaporation and retain soil moisture, the potato planting normally adopts drought resisting and water-saving technology with plastic film mulching in this area. Potato film mulching cultivation is divided into two kinds according to the operating procedure. One is the first sowing then mulching film, and covered with a layer of 3-5 cm soil on the film, relying on the soil mass and buds naturally move upward so that seedlings automatically rupture of film and natural emergence. The advantages of this approach are to solve the problem of artificial seedlings. But the disadvantage is that the film warming effect is weakened after the film is covered with soil, and it cannot be planted when the spring drought is serious. The other approach is the first mulching film then sowing, and this approach can be ridged and mulched in the autumn of previous year or in the spring of that year. It has the advantages of storing autumn moisture, resisting spring drought, raising ground temperature, etc. which can effectively solve the problem of sowing due to serious spring drought. Therefore, this approach is mostly used in this area. At present, due to the lack of matching hill-drop planter, the approach needs manual sowing, poor quality control, and labor-intensive operation, which urgently needs to be mechanized. After decades of development, China's mechanized mulching film planting technology has made great progress. The mechanism of roller wheel, vertical insertion, rotary type has been developed, and the sowing on film of corn, peanut, cotton and other crops has been realized. However, the depth of potato planting is much higher than these crops, which requires the hill-drop mechanism has a large vertical displacement and small horizontal displacement in the hill-drop process, as such to avoid tearing and picking film. Therefore, a potato hill-drop planter was designed for the potato cultivation mode with two drills sowing on ridges in the rain-fed agriculture area of the Loess Plateau in the northwest. The key components of the potato prototype was analyzed and designed, the kinematic model of the hill-drop mechanism with double crank multi-rod was established, the structure and working parameters of the hill-drop mechanism with double crank multi-rod, covering soil device and lifting soil device were determined. The scheme of transmission system was established and the working mechanism of core components was analyzed. Field experiments showed that the qualified rate of sowing depth under the film, the rate of hole dislocation, the qualified rate of hole spacing, the qualified rate of covering soil on hole and mechanical damage degree of plastic film day lighting surface were 92%, 5%, 88%, 93% and 52.1 mm/m2, respectively. Field performance experiment indexes had reached the requirements of the national and industry standards. Moreover, the results met the design requirements, which can realize integrated operation of potato hill-drop planting on film and covering soil on hole.