A cell sheet having a high hyaluronic acid production ability can be typically prepared by a method in which, on a cell culture support having a surface coated with a polymer which changes a hydration ability in a temperature range of 0-80°C, cells with increased stem cell content are cultured in a temperature range where the polymer exhibits a weak hydration ability, and then the temperature of a culture solution is changed to a temperature at which the polymer exhibits a strong hydration ability, so that the cultured cells are detached in the form of sheet.
