The invention discloses a capacitive voltage control method for a bridge current-conversion modular multi-level converter. According to the capacitive voltage control method, a current-conversion angle alpha in a phase voltage forward-direction zero crossing point in the junction between a converter transformer and a converter electric reactor in a trigger control link of the converter is changed; the breakover of the upper and lower bridge arms of the corresponding phase are switched; the capacitive voltage balance of a bridge arm sub module is maintained, so that the capacitive voltage stability of the bridge arm sub module is realized; in addition, the current-conversion angle alpha satisfies power voltage characteristics and valve group bridge arm sub module voltage-resistance requirements when the multi-level converter valve groups are switched on by the bridge arms alternatively; a feed-forward link and a feedback links are added, so that the rapidness of the capacitive voltage adjustment of the bridge arm sub module is improved; the capacitive voltage stability of the bridge arm sub module is realized; and furthermore, the operation process is simple, reliable and easy to implement, so that the capacitive voltage control method is wide in application prospects.