Abstract: In order to evaluate the spraying effects of UAVs (unmanned aerial vehicles) in tobacco fields, the effects of three types of plant oil additives (Beidatong, Maifei and Maidao) and two types of nozzles (hydraulic nozzle SX110015 and centrifugal nozzle IDK120015) on the physicochemical properties of the spray solution and the droplet deposition density and coverage of the drugs were investigated. The results showed that different types of additives reduced the surface tension and contact angle of the solution, decreased the proportion of small droplets and the relative span of the droplet spectrum, increased the droplet deposition density and coverages of droplets in the tobacco canopy, and promoted droplet uniformity. Compared to the solution without the additives, the addition of 1.0% Beidatong reduced the surface tension and contact angle of the solution on tobacco leaves by 58.8% and 64.3%, respectively. When using the SX110015 nozzle, the droplet density on the upper, middle and lower leaves of the tobacco canopy increased by 32.0%, 42.1% and 202.8%, and the droplet coverages increased by 97.9%, 106.1% and 141.5%, respectively. The proportion of droplets with a diameter of DV_0.5 increased by 13.8% and the proportion of small droplets decreased by 22.7% after the addition of Maifei. Compared with SX110015, the IDK120015 nozzle increased the droplet densities in the upper, middle and lower layers of the tobacco canopy by 92.9%, 101.6% and 160.7%, respectively. Therefore, adding Beidatong, Maifei and Maidao to the spray solution can effectively improve the effectiveness of pesticide application in the tobacco canopy. The SX110015 nozzle has high penetration, while the IDK120015 nozzle has fine droplet size and high droplet density and is suitable for spraying protective or systemic agents at wind speed ≥ 0.6 m/s.