A very safe and useful agent for inhibiting fungal growth and the like are provided by the present invention. Specifically, the present invention provides (1) an agent for inhibiting fungal growth comprising hyaluronic acid or a salt thereof excluding a heavy metal salt as the active ingredient, and a method for inhibiting fungal growth, which comprises at least a step of allowing hyaluronic acid or a salt thereof excluding a heavy metal salt to contact with a fungus, (2) an agent for reinforcing activity of inhibiting fungal growth possessed by a cell, which comprises a DNA encoding a hyaluronic acid synthase as the active ingredient, (3) a method for reinforcing activity of inhibiting fungal growth of a cell, which comprises at least a step of transfecting a DNA encoding a hyaluronic acid synthase into the cell, and (4) a method for inhibiting fungal growth, which comprises at least a step of allowing a cell transfected with a DNA encoding a hyaluronic acid synthase to contact with a fungus.
