The electronic product operation program back-up device includes main memory, CPU, serial port, auxiliary memory, multiplexer and switch. The main memory has operation program, application software and various operation relevant information stored; the CPU controls the operation of the household electronic products in LAN according to the operation program in the main memory; the auxiliary memory is for back-up of the operation program; the multiplexer serves to make the CPU use information in the main memory or the auxiliary memory optionally; and the switch is for the user to select the I/O path in the multiplexer as require. The beneficial effects of the present invention includes simple structure, high stability, etc.