The inductive power supply system comprises an input power module for receiving a stable voltage source, a storage module for storing a predetermined information, a processing module for generating a control signal according to the predetermined information and a feedback signal, a driving module for transforming the stable voltage source into a driving voltage according to the control signal, an inductive coil for electrically transmitting the driving voltage to process an inductive power transmission operation, and a feedback module for generating the feedback signal according to the driving voltage received by the inductive coil, where the predetermined information represents an initial state of the inductive power supply system comprising a sinusoidal amplitude corresponding to the driving voltage, and an intruding metal can affect another sinusoidal amplitude of the feedback signal to make the processing module correspondingly generate the control signal during the inductive power transmission operation.