Abstract: The three sets of F t curves from impulsive microthrusters tests were studied,which are used for the attitude correction of kinetic missiles or hypervelocity rockets.It is found from the study that the amount of the igniter charge can be of significant effect on the F t curves and internal ballistic performances of an impulsive microthruster,due to its ratio of igniter charge to main propellant charge being obviously different from that of conventional SRM.The amount of igniter charge must be strictly controlled so that the satisfactory internal ballistic performances can be obtained.