Method of controlling power of a fixing device of electro-photographic image forming apparatus in print standby mode

A method of controlling the power of a fixing device of an electro-photographic image forming apparatus in a print standby mode and an apparatus to perform the method includes determining whether the electro-photographic image forming apparatus is in the print standby mode. If it is determined that the electro-photographic image forming apparatus is in the print standby mode, the temperature of the fixing device is adjusted to be between a first predetermined temperature, which is a high temperature, and a second predetermined temperature, which is a low temperature. The temperature of the fixing device increases from the second predetermined temperature to an operation temperature within 10 seconds. The second predetermined temperature is 100° C. or less. Accordingly, an FPOT upon a change from a print standby mode to a print mode is maintained at about 10 seconds or less, and simultaneously power consumption in the print standby mode is reduced about 75% due to a short period of power application to a heater and a long period of cooling of the heater.