The in vitro susceptibility of a rare fungal pathogen, Mucor ramosissimus Samutsevitsch, to antimycotics in clinical use was determined. Minimal inhibitory concentrations (MICs) and minimal fungicidal concentrations (MFCs) were (MIC/MFC, μg/ml): amphotericin B, 3.125/25; miconazole, 6.25/ 6.25; clotrimazole, 25/25; fluconazole, 5-fluorocytosine, itraconazole, and ketoconazole, ≥100/100. Our results show that amphotericin B and miconazole are the most effective antimycotics.