An endoscope reprocessor includes a treatment tank configured to accommodate an endoscope, a treatment tank temperature measuring section configured to measure a temperature of a liquid in the treatment tank, a medicinal solution tank configured to store a medicinal solution, a heating section configured to heat the medicinal solution inside the medicinal solution tank, a first transfer section configured to transfer a part of the medicinal solution to the treatment tank from the medicinal solution tank, a second transfer section configured to transfer the medicinal solution in the treatment tank to the medicinal solution tank, and a control unit configured to replace at least a part of the medicinal solution stored in the treatment tank with the medicinal solution remaining in the medicinal solution tank by controlling the first transfer section and the second transfer section when a measurement result by the treatment tank temperature measuring section is lower than a predetermined threshold value.
