6-[(N-4-Fluorophenyl)amino]-7-chloro-5,8-quinolinedione(RCK3) was tested for antifungal activities, in vivo, against Candida albicans. RCK3 was compared with ketoc onazole and fluconazole in the treatment of systemic infection with Candida albicans in normal mice. The therapeutic potential of RCK3 had been assessed by evaluating their activities (survival rate) against systemic infections in normal mice. RCK3 had $ED_{50},;8.78{pm}0.18mg/kg$ but ketoconazole and fluconazole had $ED_{50},;8.00{pm}0.73,;10.00{pm}0.43mg/kg$ respectively. Intraperitoneally administered RCK3 at the $ED_{50}$, 8.78mg/kg for 7 days and 14 days reduced Candida albicans colony count in the kidneys and livers as well as ketoconazole and fluconazole at these $ED_{50}$, 8.00 and 10.00mg/kg. And administered RCK3 at the $ED_{50}$ for 14 days improved survival rates better than ketoconazole.