A system for supplying adapted power to an electronic device with a reduced level of power consumption when the device is not in use includes a first power supplying module, a control module coupled to the first power supplying module, and an MCU coupled to the control module and coupled to the electronic device. The MCU is configured to switch on the first power supplying module when the first power supplying module is in a normal state, the normal state being an AC power supply coupled to the first power supplying module. The MCU detects an instant mode of the electronic device and outputs a first signal to the control module when the electronic device is in a standby mode. The control module is configured to switch off the first power supplying module when the first signal is received. A power supplying method is further provided.