The occurrence of Candida albicans in patients with urinary tract infections, and in vitro of C. albicans to a urinary catheter were studied. C. albicans was more adherent to latex rubber than to silicon, whereas C. tropicalis adherence was the reverse. The relationship between the adherence and the change in interfacial free energy which corresponds to the process of adherence, suggests that hydrophobic interactions are involved in candidal adherence to catheter materials. Among five N-acyl-phenylalanines, N-octyl-phenylalanine showed outstanding ability in removing adherent fungi on catheter surfaces.