This is a case report of mediastinal fungal granuloma in an immunocompetent host. The definite diagnosis was made by pathological biopsy via video-assisted thoracoscopy and silver methenamine staining showed aspergillus hyphae and spores in the epithelioid granuloma. In conclusion, opportunistic pathogenic fungi can cause granulomatous inflammation in mediastinal lymph nodes in an immunocompetent host, as it can do in an immunocompromised host. More attention should be paid on tissue biopsy and pathological examination to ensure a correct diagnosis for these kinds of cases.