An ethnobotanical study on medicallyimportant plant roots was conducted in Argao, Naga, San Fernando, San Remigio of Cebu Island, Philippines. A total of 25 informants from each study sites were interviewed (bisaya’ng mananambal). The study recorded 18, 22, 16, 21 different species of plants claimed to have medicinal uses. The most common ailment cited by the traditional healers is ‘relapse’, which has the highest number of cited plants used for treatment. The modes of preparation are either concoction or decoction. The common mode of administration is oral intake, by drinking the wine or the water from concocted or decocted root/s as needed and until the ailments get well. The effectiveness of the medicinal plants used by the traditional healers vary from each study site according to perceived effectiveness of each plant used. The medically-important plant roots cited by the traditional healers from the four municipalities reported to be very effective in treating ailments/diseases are the mandalusangputi [Justiciasp] in Argao, mangagaw [Euphorbia hirta Linn] in Naga, kapayas nga laki [male Carica papaya] in San Fernanado), and wachichao [Orthosiphonaristatus] in San Remigio.