The antifungal activity of nyasol (NYS) alone or with various antifungal agents was measured in vitro against Candida albicans, Aspergillus fumigatus, and Trichophyton mentagrophytes. NYS is a compound recently purified from a medicinal plant, Anemarrhena asphodeloides. Among 12 agents, miconazole (MCZ), ketoconazole (KCZ), clotrimazole (CTZ), and cerulenin showed marked synergistic effects against C. albicans. The fractional inhibition concentration (FIC) indices against 4 strains of C. albicans were 0.067-0.31 for MCZ plus NYS, 0.078-0.31 for KCZ plus NYS, and 0.098-0.13 for CTZ plus NYS. These values indicate the possibility of using NYS as an adjuvant to azole agents in the chemotherapy of candidiasis.