A power supply monitoring system with power supply apparatus is operated by a software instruction. The power supply monitoring system includes a computer motherboard, a power supply, and a microprocessor. The microprocessor built in the power supply and coupled to an electro-thermal adjusting unit of the power supply; a transmission line, for connecting the microprocessor to a transmission interface of the computer motherboard; and a power supply status monitor program, for displaying operating status information of the power supply and providing a software instruction to control the electro-thermal adjusting unit of the power supply.