Disclosed is an image forming apparatus capable of controlling a fuser thereof to operate effectively even with a possible fluctuation in the AC voltage input. The image forming apparatus may include an input for receiving an AC voltage, a detector that outputs a DC voltage corresponding to a level of the AC voltage input, a fuser operable to produce heat according to the AC voltage input, a storage in which fusing temperature control information and a controller that controls the fuser using the fusing temperature control information corresponding to the DC voltage.