Abstract: Studies the design of tail wings and their effects on the ballistics and velocity of submunitions.Wind tunnel tests were performed on submunitions with different tail wing sizes to get the aerodynamic characteristic parameters.Relations between the aerodynamic drag and flight velocity are obtained.Combined with particle ballistic equations,the effects of tail wing sizes and initial angle of pitch on the submunitions ballistic and velocity are calculated and analyzed.Results of analysis show the submunition velocity can be reduced to less than Mach number 1 at the height of 15?000?m when the tail wings area nearly equals the maximum cross section area of the submunition body,for the initial condition of ballistic height of 5 000 m,initial velocity of 6Ma and angle of pitch of -75°～(-45°.)