The invention discloses a self-adapting wireless electric energy transmission device and belongs to the technical field of wireless electric energy transmission. The self-adapting wireless electric energy transmission device comprises a transmitter, a receiver, a transmitting LC harmonic oscillator, a relay LC harmonic oscillator and a receiving LC harmonic oscillator, wherein the transmitter comprises a transmitting coil, a microcontroller, an electrically-controlled oscillator, a power amplifier and an impedance transformer, the receiver comprises a receiving coil, an impedance transformer, a rectifier bridge and an output terminal, and the transmitting LC harmonic oscillator, the relay LC harmonic oscillator and the receiving LC harmonic oscillator are of the same structure and are respectively provided with a resonance coil, a frequency range electronic switch, a resonance capacitor and a control circuit. The self-adapting wireless electric energy transmission device is simple in structure, capable of automatically adjusting the transmitting frequency and the resonant frequency according to the electromagnetic frequency in the environment, high in transmission stability, capable of achieving long-distance transmission by adopting a plurality of relay LC harmonic oscillators.