The invention relates to the technical field of wireless power supply, in particular to a relay wireless power supply system based on magnetic resonance. The relay wireless power supply system comprises a frequency generator module, a transmitter module, a relay module, a receiver module, a high frequency rectifier module and a voltage regulator module, wherein the signal output end of the frequency generator module is connected with the signal input end of the transmitter module, an output signal of the transmitter module is spread to the relay module via a free space, the output signal of the relay module is spread to the receiver module via the free space, the signal output end of the receiver module is connected to the signal input end of the high frequency rectifier module, the signal output end of the high frequency rectifier module is connected to the signal input end of the voltage regulator module, and the signal output end of the voltage regulator module is connected to a load. The relay wireless power supply system can get rid of the limitations of a wired power supply, avoid the inconvenient wiring of a power supply conducting wire, be particularly applicable to application environments which are inconvenient to carry out the wiring, such as medical implants, sensor networks which are related to Internet of things and the like.