The invention puts forward a modular multilevel converter (MMC) hierarchical control method. On the basis of the existing voltage-current and sub module control method, a current injection ring current suppression structure, a sub module capacitive voltage ripple suppression structure and a predicted composite voltage frequency and amplitude recovery control method are superimposed. Hierarchical control is divided into inner-ring basic control and outer-ring optimized control. The hierarchical control method is applicable to half-bridge sub module, full-bridge sub module and mixed-bridge sub module multilevel circuits. Inner-ring control comprises a voltage and current loop control structure, a sub module capacitive voltage ripple control structure, a ring current injection suppression control structure, and the like. Outer-ring control comprises a droop control structure, a predictive composite control structure, and the like. Ring current injection suppression control, sub module capacitive voltage ripple control and predictive composite control methods are put forward by the invention. The control method of the invention can help improve the stability of a system under different load conditions, improve the quality of output voltage and power of a DC transmission system, reduce the investment cost of a modular multilevel transmission system, and improve the anti-interference ability and rapid response ability of a transmission system.