The embodiment of the invention provides a wireless charging method and system and a mobile terminal. The wireless charging method comprises the steps that a first mobile terminal and a second mobile terminal start a wireless charging function; the first mobile terminal is confirmed to be a transmitting side of wireless charging, and the second mobile terminal is a receiving side of wireless charging; and wireless charging is performed on the second mobile terminal by the first mobile terminal. With application of the wireless charging method, a problem of insufficient electric quantity of the mobile terminal under the emergency situations can be solved, and operation is easy and use restrictions are less.