Worldwide, tuberculosis (TB) is a major human killer claiming about 1.5 million lives per annum. Medicinal plants are believed to serve as a source for products that can serve as anti-TB agents. Despite the importance of plants for human health and subsistence in both developed and developing countries, loss of biodiversity-based cultural knowledge and traditions is a commonly reported phenomenon, therefore, documenting such knowledge before it disappears completely is a necessity. The study was carried out to document medicinal plants that are traditionally used for the treatment of TB in the eastern region of O.R. Tambo district, Eastern Cape Province of South Africa. Information about plants (names, parts and methods of preparation) that are used for treating TB was gathered from traditional medical practitioners (TMP) using questionnaires. Twenty-four plant species belonging to 19 families that are used for the treatment of TB were revealed by this study. The Apiaceae, Amaryllidaceae, Asparagaceae, Compositae, and Leguminosae were the most prominent, represented by two species each. Out of the 24 plants reported, Protorhus longifolia (Bernh.) Engl (Anacardiaceae), Phymaspermum acerosum Källersjö (Compositae) and Strychnos henningsii Gilg (Loganiaceae) were the most frequently mentioned species, and were reported for the first time for TB treatment. Most of the plants (91%) documented are administered orally; the root (54%) is the most common plant part used, while decoctions and infusions are the main preparatory methods. Indigenous knowledge of medicinal plants used in the treatment of TB exists in the eastern region of O.R. Tambo district, and TMP still play an important role in delivering primary health care services. The ethnobotanical information about the plant species mentioned in this study may serve as baseline data for future studies on their pharmacological effects and to identify those that have potential in the development of anti-TB drugs.