We devised a transparent anorectoscope for internal hemorrhoidal sclerotherapy. Using this scope the grade of hemorrhoids of the patients can be evaluated accurately through the transparent wall of the scope, and the device facilitates easier and safer sclerotherapy under clear direct vision, compared to the conventional free-hand-style treatment. We conclude that sclerotherapy using this anorectoscope represents a minimally invasive treatment for low-grade internal hemorrhoids and is recommendable for outpatient therapy of internal hemorrhoids.