There is provided a temperature control unit for an electrophotographic photoconductor substrate, containing a stretchable membrane member which is detachably disposed in a hollow space of the cylindrical substrate, wherein the membrane member is configured to sequentially stretch until reaching the deepest part of the hollow space of the cylindrical substrate as a result of an introduction of a refrigerant therein to closely contact with an entire inner wall of the cylindrical substrate, and to sequentially shrink to the original shape thereof as a result of a release of the refrigerant therefrom, so that the membrane member is detachably disposed in the hollow space, and wherein the membrane member is configured to make a heat transfer between a surface of the cylindrical substrate and the refrigerant via the membrane member closely contacted with the inner surface of the cylindrical substrate, to control a surface temperature of the cylindrical substrate.