A fixing device includes a fixing member, a heat source for heating the fixing member, a pressure member urged against the fixing member so as to form a nip portion between the pressure member and the fixing member, and a release agent applying unit that applies a release agent to the fixing member or the pressure member. An amount A (weight parts) of wax contained in the toner, and an amount B (mg/sheet) of a release agent applied to the fixing member or the pressure member by the release agent applying unit per printing medium of A4 size satisfy the following relationships (1) through (3): 0.ltoreq.A.ltoreq.20 (1) 0.ltoreq.B.ltoreq.1.0 (2) 8.ltoreq.A+(12.times.B).ltoreq.32. (3)