The purpose of this study was to document Melanau knowledge of medicinal plants in Balingian, Mukah, Sarawak. Information was obtained from semi-structured interviews, personal conversations with practitioners and direct observations. Our data covered 43 species of medicinal plants belonging to 28 families. We found that most species are for post-natal (10 species) and hypertension (7 species), disorders which are prevalently and primarily treated with medicinal plants. In the treatments, the plants are used mainly as food and drinks (Averhoa carambola, Carica papaya, Nephrolepis bisserata, Cocos nucifera, Centella asiatica and Curcuma longa), medicinal baths and externally. Fast disappearance of the traditional culture and natural resources due to urbanization and industrialization suggests that the unrecorded information may be lost forever. Thus, there is an urgent need to record this valuable Melanau medicinal knowledge and keep it for the next generation.