We have found, to our knowledge, the first case of tinea corporis due to Aphanoascus fulvescens (Cooke) Apinis recognized in the United States. The organism, a keratinophilic soil saprophyte, was repeatedly isolated from a 21-year-old white male student. The 4 × 5-cm, red, scaling patch had developed on the inner aspect of the right thigh and subsequently spread to other areas of the leg three weeks after the patient had worked as an animal handler in Montana.