The invention discloses a modular direct current power flow controller. The modular direct current power flow controller comprises n direct current power flow controller groups and m capacitors, wherein each direct current power flow controller group comprises m direct current power flow control modules which are connected in series orderly; and each direct current power flow control module comprises 4 IGBT (Insulated Gate Bipolar Translator) tubes T1 to T4 and anti-parallel diodes of the 4 IGBT tubes. The modular direct current power flow controller provided by the invention effectively inherits the advantages of a direct current power flow controller in the prior art, and compared with the prior art, each direct current power flow control module only comprises four IGBT tubes T1 to T4, and the number of the IGBT tubes is smaller than that of the prior art, and the reduction of the number of the IGBT tubes can effectively reduce the operation mode of power flow control equipment, and reduce the complexity of a control strategy; besides, by connecting the m direct current power flow control modules in series orderly, the condition of series operation of the IGBT can be effectively avoided, and the trigger consistency requirement of the IGBT tubes can be reduced; moreover, the modular design method can effectively reduce the equipment failure maintenance cycle, and reduce the influence on the normal operation of an entire system.