A method and a system for adjusting a double-sided LCC compensation network of a wireless charging system are provided. The method includes: obtaining a standard coupling coefficient, a rated operating frequency, and rated parameter values of compensation elements in the wireless charging system; determining change rates of output performance of the wireless charging system; determining an adjustable compensation element; obtaining a real-time coupling coefficient between the primary-side transmitting coil and the secondary-side receiving coil; determining whether the real-time coupling coefficient is less than a coupling coefficient threshold; and adjusting an operating frequency of the wireless charging system when the real-time coupling coefficient is not less than the coupling coefficient threshold; or adjusting both an operating frequency of the wireless charging system and the adjustable compensation element when the real-time coupling coefficient is less than the coupling coefficient threshold.