The present invention relates to a valve basic control device and method of a module multilevel converter. The module multilevel converter is provided with a bridge arm including a plurality of cascaded sub-modules, and the converter valve basic control device in a hierarchical control architecture, that includes: a current control unit, used for controlling a current of the converter, generating an input number of the sub-modules of the bridge arm in real time, obtaining a current direction of the bridge arm and sending number information and current direction information; a bridge arm summary control unit, used for determining sub-modules to be input or removed according to the received state of each sub-module and the number information and the current direction information received from the current control unit, and sending a determination result; and a bridge arm segmented control unit, used for inputting or removing the sub-modules according to the determination result received from the bridge arm summa
