Indigenous knowledge on the usage of medicinal plants all over the world precedes the origin of modern medicine in healthcare system. Plants have given many health benefits to humans since ancient times. Drynaria quercifolia commonly called Oak Leaf Fern, is used in traditional medicinal system by different groups of people to treat various kinds of health problems however, in Ayurvedic System of Medicine it is sold in the name of ‘Ashwakatri’. The present study aims to document the traditional medicinal knowledge on Drynaria quercifolia in the Kodagu district. The folk knowledge believes that the host specific Drynaria quercifolia has considered as strong and effective medicine. This ferns collected from only specific tree species can be extracted for its medicinal value. Paper also deals with the tradition information on the preparation and consumption of folk medicine. Though the medicinal uses of Drynaria quercifolia has been described by many workers, the practice of traditional medicines significantly varies from region to region and also in the similar location of the same region. The survey was conducted in the Kodagu district of Karnataka to document the traditional medicinal usage of fern Drynaria quercifolia. To generate the information on traditional knowledge, frequent discussions and semi-structured interviews with folk healers viz., natividyas, knowledgeable individuals and forest tribes. Based on the results of the study it is found that this species is used for curing jaundice as folk medicine and the medicinal value of the fern which is extracted only from those individuals growing on specific host trees viz., Artocarpus hirsutus, Ficus mysorensis, F. benghalensis and Mangifera indica have found the effective results than the species growing on other trees. Study concluded that the host specific trees of Drynaria quercifolia are more effective in treating ailments.