an image forming apparatus for forming an unfixed image on a recording material includes a fixing device having a pair of rotatable members for holding therebetween and conveying the recording material to fix the unfixed image on the recording material , speed control device for variably controlling the fixing rotational speed of the pair of rotatable members to a first fixing speed and a second fixing speed lower than the first fixing speed , application apparatus for intermittently supplying a parting agent to at least one of the pair of rotatable members , and application control apparatus for variably controlling the application acting period of the application apparatus in accordance with the fixing rotational speed of the pair of rotatable members variably set by the speed control device .