Abstract: A qualitative analysis has been undertaken for the special moving state of spraying particles with lots of filming on the technologic proccss of are spraying by high speed camera.The "oblique circular target" method for the performance of three-dimensional display of particles has been deducted.specd of the particles has been calculated by means of a special mathematical The flowing model with electronic computer so that the time-spacc recording ability of high speed photography may be enhanced.The result presented in this paper could be used as a theoretical basis for the selecting of optimum arc spraying parameters and the improving of spraying gun design.