Two isolates of Cunninghamella bertholletiae from confirmed cases of human zygomycosis were studied, and their sexual, asexual, and physiologic characteristics described. Minimal inhibitory concentrations for these two isolates, as well as for six other clinical isolates of C bertholletiae, were determined for amphotericin B, flucytosine, and miconazole using a standardized agar dilution technique. All isolates were found to be susceptible to miconazole, but resistant to flucytosine and amphotericin B.