The invention relates to an efficient electric vehicle direct-current fast charge system, and belongs to the field of new energy vehicles. The efficient electric vehicle direct-current fast charge system comprises a pile of a direct-current fast charge pile, output direct-current bus, an AC / DC converter, a DC / DC converter, a capacitor, a power distribution transformer and a power grid. One end ofthe power distribution transformer is connected to the power grid, the other end of the power distribution transformer is connected to an AC end of the AC / DC converter, and a DC end of the AC / DC converter is connected with the output direct-current bus of the electric vehicle direct-current fast charge pile; one end of the DC / DC converter is connected with the capacitor, the other end of the DC / DCconverter is connected with the output direct-current bus of the direct-current fast charge pile, and low-order harmonic waves in AC / DC direct-current output currents can be absorbed by the other endof the DC / DC converter under the control. The efficient electric vehicle direct-current fast charge system has the advantages that secondary-side winding transformation ratios of the power distribution transformer are designs, accordingly, three-phase alternating-current-side voltages can be reduced, and requirements of minimum values of voltage ranges of battery packs of mainstream electric vehicles can be met by AC / DC direct-current output; only single-stage AC / DC power conversion is required, only harmonic currents are absorbed by the low-power DC / DC converter, the problem that all chargepower is transmitted through extra DC / DC converters can be solved, accordingly, the cost can be saved, and the efficiency of the efficient electric vehicle direct-current fast charge system can be improved.