The disclosure provides a balanced-current circuit structure and a parameter design method for a bifilar winding coil of wireless power transfer. The disclosure relates to the technical field of magnetic coupling wireless power transfer. The circuit includes a bifilar winding coil, a compensation capacitor array and a controlled voltage source array. The bifilar winding coil includes a first coil and a second coil, the compensation capacitor array includes a first compensation capacitor and a second compensation capacitor, and the controlled voltage source array includes a first controlled voltage source and a second controlled voltage source. Compared with the existing centralized series compensation scheme, the scheme proposed by the disclosure can realize the currents in two windings of the bifilar winding coil being basically the same, so as to eliminate the current imbalance problem existing in the traditional compensation mode, thereby fully exerting the current-carrying capacity of the bifilar winding coil, and improving the practicability of the bifilar winding coil in practical applications.