PURPOSE: To minimize the temp. difference in the longitudinal direction of a roller and the unequal temps. in a narrow region, to attain short warm-up time and low electric power consumption and simultaneously to realize fixing with high quality.

CONSTITUTION: This heating roller 20 for fixing is produced by using a heat resistant material mixed with at least two conductive materials having different resistivities for a resistance heating element layer 14 and changing the mixing ratios of the conductive materials by the position of the heating roller surface. Carbon and silver are used as the conductive materials and a polyimide is usable for the heat resistant material as more specific materials. The ratio of the carbon is merely necessitated to be increased in a place where the resistance value is desired to be increased and the ratio of the silver to be increased in a place where the resistance value is desired to be decreased. Since the heating roller 20 is generally larger in the heat release quantity at both ends than at the center, the temp. over the entire part is preferably set nearly constant by setting the calorific values at both ends larger than in the central part. The resistance value of the resistance heating element 14 is necessitated to be set large at both ends and small in the central part.