Changes in the cell wall of yeast-like fungi Candida albicans caused by bacterial enzyme lyticase were studied under an electron microscope. The results were compared with the findings on phagocytosis of lyticase-treated Candida albicans by rat alveolar macrophages. It was shown that destruction of the mannan and fibrous outer layers of the cell wall of yeast-like fungi treated with the enzyme led to the release of intracellular organelles and their content. Lyticase treatment reduced the resistance of Candida albicans to intracellular digestion by macrophages contributing to completion of phagocytosis.