The paper present the results of a research study on developing an electrostatic spraying nozzle for green house application. A twin fluid nozzle specially constructed for generation of very fine water based pesticides spray was used in this study. The influence of position and shape of the electrodes on spatial distribution of electric field required to charge the spray to a desired level of specific charge was established by applying a reverse field modelling technique. A finite element computer software ALGOR® was utilised for this purpose. The electrode arrangement was successively modified until the optimum shape and geometry were obtained. The size distribution as well as charge to mass ratio of the spray generated by the nozzle was systematically measured under various operating conditions. The result of preliminary experimental study confirmed that the improved design enhanced the deposition characteristic of the charged spray.