In some occasions, Inductively Coupled Power Transfer (ICPT) systems are required to transmit bidirectional data. In order to realize this purpose, a full duplex data transmission method is proposed in this paper. The power transmission system adopts the inductor/capacitor/capacitor-series (LCC-S) compensation structure to realize the constant voltage output of secondary coil. In the signal transmission system, the forward and reverse signal transmission systems adopt Amplitude Modulation (AM) technology and Amplitude Shift Keying (ASK) technology, respectively. And a frequency selective network is added to avoid interference between forward and reverse signal transmission. Then the feasibility of the scheme is verified theoretically by circuit simulation software Multisim, and the optimal element parameters are selected according to the calculation and simulation results. Finally, a hardware circuit is built to thoroughly verify the feasibility of the scheme.