Abstract: In order to solve the problem that the current sprayer seed supply device is not suitable for coated seeds, this study combines the methods of physical and simulation tests to spray coated lemon strip seeds as the object, aiming at reducing the breakage rate of seed row and improving the uniformity of seed row, and designed a 4BQD-40 type sprayer spiral seed supply device. Firstly, the parameters of the seed supply device are calculated and the structure design is carried out according to the motor parameters, maximum spraying amount and seed rest angle determined by the planter. Then, three discrete element simulation models of seed supply devices with different parameter configurations are established and the seed arrangement process is simulated, and the optimal parameter ratio of spiral blade diameter of 80mm, spiral blade pitch of 60mm, spiral shaft diameter of 28mm and diameter of seed discharge port is obtained according to the force of seeds and the continuity of seed displacement during the seed displacement process. Under the same working requirements, the discrete element simulation of the seedling process of spiral and grooved wheel seed supply devices is carried out. Finally, the crushing rates of the two were measured under the same seed supply group, and the crushing rates under the five seed supply volumes of the original trough wheel seed supply device were 17.68%, 14.90%, 12.88%, 12.45%, and 11.78%. The crushing rate of the spiral seed supply device under the same seed supply amount was 2.11%, 2.65%, 2.91%, 3.01% and 3.37%, and the experimental results showed that the seed crushing rate of the spiral seed feeding device coated lime strip was significantly reduced.