A burning spray is photographed by means of a double-flash method which is improved to make perspective positions of droplets on a photograph measurable. It is by this method that the number density and the velocity of droplets can be measured quantitatively on the photograph. Further, owing to the indirect measurement of the burning velocity of a droplet in the spray, an equation is derived from the law of conservation of the number density. The equation is applied to analyze the experimental data. Thus, the burning velocity and moreover the path of the droplet are estimated. Consequently, it is made clear that the relation between dimensionless numbers is in fairly good agreement with that reported in the literature of single droplets. However, in the burning spray, the drag coefficient is rather low about small droplets.