This paper used Bond-Space theory to analyze the electromechanical dynam ics of Ga lting w eapon startup systems. The Bond-Spacemodel and vector state equations of the systems w eremade. The coupled characterist ics for the series and separate excitation DC ( D irect Current) motor w ere calcu lated in the state o f the d irec-t startup, step-dow n startup and alter-resistance startup. The calcu lated results can supply the theoret ical bases for test ing pro totype design.