A three-phase power apparatus with bidirectional power conversion applied to charge a battery of an electric vehicle. The three-phase charging apparatus includes an AC-to-DC conversion unit, a first DC bus, a first DC-to-DC conversion unit, a second DC bus, and a second DC-to-DC conversion unit. The first DC bus is coupled to the AC-to-DC conversion unit. The first DC-to-DC conversion unit includes an isolated transformer, a resonant tank, a first bridge arm assembly, and a second bridge arm assembly. The first bridge arm assembly is coupled to the first DC bus and a primary side of the isolated transformer. The second bridge arm assembly is coupled a secondary side of the isolated transformer. The second DC bus is coupled to the second bridge arm assembly. The second DC-to-DC conversion unit is coupled to the second DC bus and the battery.