BackgroundTermitomyces clypeatus (T. clypeatus) is an edible mushroom specie which grows in various areas in Cameroon. It is indicated by several healers in treatment of several infectionsand is frequently used for this purpose. However, no study has been reported on its antibacterial and immunomodulatory activities which were the aim of this study.MethodsDisc diffusion method was used to appreciate the bactericidal activity against 4 bacteria and 2 yeast species. The immunomodulatory activities were assessed in mice, where the extract was administered by gavage and as supplement in the feed. The treatment was done for 10 days. Delayed type hypersensitivity test was carried out to assess the cell mediated immune response while the effect on humoral immunity was evaluated using hemagglutination assay and mice lethality test.. The body weight was also recorded in mice used for delayed hypersensitivity.ResultsIt was found that extract of T. clypeatus highly inhibited the growth of bacteria and yeast at different ratios compared to the medium (P < 0.05). The extract of T. clypeatus has reversed the immunosuppressed effects of dexamethasone on antibody formation. In addition, it significantly decreased of the mice lethality rate in mice infected by Pasteurella multocida (P < 0.05). Administration of T. clypeatus also significantly increased the delayed type hypersensitivity response in healthy and dexamethasone immunosuppressed mice (P < 0.05), but it significantly reduced the body weight of mice after 10 days.ConclusionThe results provided basic information demonstrating the antibacterial activity and immunostimulatory activity of T. clypeatus on both cell-mediated and humoral immunity.