This paper analyzes the factors that affect jetting projectile formation of shaped charge through numerical simulation. Grey relational degree of each factor is obtained from grey relation theory. It is suggested that altitude, thickness of the liner wall and Apex angle of liner,as well as altitude of shaped charge are the main factors affecting formation performance of jetting projectile. Jetting projectile formation is controlled by thickness of the liner wall seriously; and the tip and tail velocity difference of jetting projectile is affected by Apex angle of liner. The analysis indicates that the grey theory is a useful way to determine line parameters in liner design.