Abstract: Abstract: The seed potato distribution is not uniform, and the seeding quality and quality of back fill is poor when potato seed casting into the furrow by using the ditching shoe and disc opener. In this study, the splitter sliding-knife potato opener was designed and optimized. It had a good embedded performance. The opener was towed by a tractor when the potato planter was operation. The installation site was under the seed-metering device and the longitudinal direction of opener can be adjusted to requirements. A V-shape furrow was got after the working process of opener. The soil particles were cutting and crashed by the edge of the shovel at the front side of the opener, and moved along the side surface of opener. Some of soil particles were fall into the furrow firstly to create a soft furrow thus providing a better furrow situation for potato to grow. In this paper, we also obtained the main factors that influenced soil covering for seed potato, by analysis of the soil particles in the process of motion on the side of the opener and the process of soil fall into furrow, and also kinematics analysis the seed potato falls into the furrow. The time at which the soil particles contact the bottom of the furrow was less than the time at which the soil particles fall into the furrow at the range of the resting angle. The planting effects were not only influenced by the parameters of opener, but also had a connection with the position of potato casted into furrow. The ideal seeding condition is that the potato fall into the bottom of the V-shape furrow, the lateral deviation coefficient of the seed potato is well, and the sowing quality is higher. To get good effects of planting, the time of potato fall into furrow should be less than that of soil particles fall back into furrow. The factors influencing the effect of the potato seed in the ditch were obtained through theoretical analysis after the movement parameters of planter were collected, and they were forward speed, depth of furrow, the length of opener and side angle of opener when initial conditions of the seeding were determined. A rotating orthogonal field experiment was designed. With forward speed, side angle of opener, length of opener and depth of furrow were taken as the experiment factors, coefficient of variation of row spacing, sowing width mean absolute deviation and quality of back fill as the test indices. The test was implemented in Heilongjiang Academy of Agricultural Sciences in June, 2015. The results showed the primary and secondary order of influencing factors for each test index. For the coefficient of variation of row spacing, the order was the depth of furrow, forward speed, the length of opener and side angle of opener. For the sowing width mean absolute deviation, the order was the depth of furrow, forward speed, side angle of opener and length of opener. For the quality of fill back, the order was the depth of furrow, forward speed, the length of opener and side angle of opener. The best structure parameter of splitter sliding-opener was obtained through field test. And results showed that the coefficient of variation of row spacing was 10.8%, sowing width mean absolute deviation was 3.83 mm, the quality of fill back was 24.1%, when the forward speed was 0.95 m/s, the opener of the side angle was 60 degree, the opener length was 500 mm, the depth of furrow was 115 mm. The comparison test showed that the V-furrow out of slide-knife opener was better than the ditch out of the traditional shoe-type opener. The reason was that the V-furrow can reduce seed movement and lateral displacement, to improve the consistency of the seed space. Besides, when the combination of the length of slide-knife opener was 500 mm and the side angle of the opener was 60°, the machine can provide enough time for potato seed into furrow, and the quality of fill back was also large so that potato seed can have enough soil cover and have a good ambient temperature and humidity for its growth. The sowing quality for the splitter sliding-opener was better than traditional opener. The opener designed was meeting the requirements of potato planting. The study of potato furrowing seeding device provided with reference to the design of a new theoretical support.