The processing of agricultural crops using unmanned aerial vehicles is accompanied by the drift of the aerosol cloud under the influence of wind and the uneven density of droplet deposition on the surface of plants. We can improve the processing efficiency by implementing an electrostatic charging system for working fluid drops. (Research purpose) The research purpose is in preparing an analytical review of existing systems for electrostatic charging of working fluid droplets on unmanned aerial vehicles. (Materials and methods) Authors reviewed patents, scientific papers in the field of development, evaluation of the operation parameters and efficiency of the electrostatic spraying system of working fluid on unmanned aerial vehicles. The article gives criteria for the effectiveness of the electrostatic spraying system. (Results and discussion) Authors have described the main method of electrostatic charging of droplets, which has proven itself according to such criteria as safety, energy consumption and design simplicity. The article describes an electrostatic spraying system, the design and operating principle of which are the basis of modern systems for electric charging of working fluid drops installed on ground and aviation equipment. Authors found out the optimal flight altitude, which provides the highest density of working fluid drops on the treated surface. (Conclusions) The use of an electrostatic spraying system on unmanned aerial vehicles increases the density of droplets of sprayed liquid by 33 percent. The article shows that the use of nozzles with a fan-shaped spray torch reduces the distance of aerosol droplets drift in a crosswind by 1.5-2 times compared to nozzles with a cone-shaped spray torch. The electrostatic spraying system slightly increased the density of droplet deposition in the lower part of the plants (targets).