A low-loss data transmission method used in a high-power induction-type power supply system consisting of a supplying-end module and a receiving-end module is disclosed. The supplying-end microprocessor of the supplying-end module has built-in anti-noise signal analysis software that can remove noises from the data signal fed back by the receiving-end module, assuring high stability of the transmission of data signal and reducing energy dissipation of data transmission. Subject to a special circuit arrangement of the receiving-end coil of the receiving-end module, signal modulation is performed on a low voltage DC square wave, assuring a high level of stability of the supplying of power supply to the receiving-end module.