Abstract: Because of its flexible and accurate characteristics, plant protection UAV has been developing rapidly in the global scope. In order to obtain relatively good eppo unmanned aerial vehicle（UAV） spray droplets deposition effect, this paper applied electric four rotor eppo UAVs administer tests are carried out in the process of winter wheat grass, the nozzle type（anti floating nozzle type DG11003 and original nozzle SX11001 VS） and spray amount（7.5, 15.0, 22.5, and 30.0 L/hm~2） on the droplets deposition distribution, the influence of parameters for optimizing eppo UAV field weeding work provides reference data. Droplet deposition parameters, including droplet coverage rate and droplet deposition density at different sampling points, were analyzed by DepositScan software. The test results showed that the number of droplets of the anti-drift nozzle DG11003（27.9～73.0 droplets/cm~2） was significantly greater than that of the original nozzle SX11001 VS（13.7～47.2 droplets/cm~2）. But there was no significant difference between the number of droplets and the droplet coverage rate, and the variation ranges of which was 2.1%～10.4% and 2.0%～9.9%, respectively. At the same time, the droplet coverage rate and the number of droplets increased with the increase of spray volume. According to the variation coefficient differences of droplet deposition under different treatments, it could be seen that spray volume had no significant effect on the uniformity of droplet deposition. However, the influence of the two nozzle types on droplet deposition was significantly different in the process of winter wheat herbicide spraying. The variation coefficient of anti-floating nozzle DG11003 was small, and the effect on droplet deposition was better. Its droplet coverage rate and the number of droplets variation coefficients varied from 43.6% to 73.4% and 46.0%～49.4%, respectively. This study discussed the effects of spray volume and nozzle type on the deposition and distribution of droplets on the wheat canopy when eppo UAV were used to spray winter wheat herbicides. Comprehensive analysis showed that the best effect was when the anti-floating nozzle DG11003 was used for spraying under the condition of large spray volume. This research could provide reference and guidance for the rational spraying of herbicides in wheat fields by eppo UAV.