To provide a safety power feeding device and method for audio visual reproducing system.

A central processor is provided with an information processing operating program 60 including a program 62 for closing and saving the file of an information processing system and a start-up program 61. A safety power feeding device comprises a means 4 for detecting a voltage drop, in which a constant voltage supplied by the main power supply 2 becomes lower than the constant limiting value, storage means 11, 12, 13 for almost instantaneously storing the power connected to an emergency power supply 10 for supplying power sufficient for the operation to the central processor 6 by a circuit which is connected on one hand to the current source 1 and meanwhile automatically substitutes the main power supply 2 with the emergency power supply 10 and a means 5 for starting the save procedures after the lapse of a constant time interval.