Provided is a process for producing a regenerated hydrotreating catalyst by regenerating a spent hydrotreating catalyst in a prescribed temperature range, wherein the prescribed temperature range is a temperature range of T1−30° C. or more and T2+30° C. or less, as determined by subjecting the spent hydrotreating catalyst to a differential thermal analysis, converting a differential heat in a measuring temperature range of 100° C. or more and 600° C. or less to a difference in electromotive force, differentiating the converted value twice by temperature to provide a smallest extreme value and a second smallest extreme value, and representing a temperature corresponding to the extreme value on the lower-temperature side as T1 and a temperature corresponding to the extreme value on the higher-temperature side as T2.