The invention belongs to the technical field of direct-current converters, particularly relates to a three-phase CLLC bidirectional direct-current converter and a control method thereof, and aims at solving the problems that the existing high voltage side series-low voltage side parallel structure based on modularization is large in number of modules, the reliability is poor, and the existing converter based on a multi-level technology is complex in circuit topology, uneven in capacitance voltage division and high in clamping tube voltage stress. The three-phase CLLC bidirectional direct-current converter comprises a high-voltage side voltage-dividing capacitor module, a three-phase half-bridge series / parallel module, a three-phase primary side / secondary side resonance module, a three-phase isolation transformer and a low-voltage side capacitor module, wherein the high-voltage side voltage-dividing capacitor module comprises three voltage-dividing capacitors; the three-phase half-bridge series / parallel module comprises three bridge arms which are connected in series / parallel, and each bridge arm comprises two switching tubes which are connected in series; the three-phase primary side / secondary side resonance module comprises an a-phase primary side / secondary side resonance cavity, a b-phase primary side / secondary side resonance cavity and a c-phase primary side / secondary side resonance cavity; and the three-phase isolation transformer comprises a single-phase transformer a, a single-phase transformer b and a single-phase transformer c. High-voltage side voltage division iscarried out through the voltage-dividing capacitor, the voltage stress of a clamping tube is reduced, the switching loss is reduced through the high-frequency soft switching technology, and the efficiency and the power density of the converter are improved.