Provided is a means for more efficiently generating ice which has a high cooling capacity. A flake ice production device 10 generates ice by cooling the wall surface of an inner cylinder 22 and freezing brine that has adhered to the wall surface of the cooled inner cylinder 22. A spraying unit 13 supplies brine to the wall surface of the inner cylinder 22 by causing the brine to adhere thereto. A stripping unit 14 collects the ice generated on the wall surface of the inner cylinder 22. In addition, the flake ice production device 10 is designed such that formula (1) is satisfied when Y represents an ice making speed indicating the amount of ice generated on the wall surface of the inner cylinder 22 per unit time, and x1 represents the thermal conductance rate of the wall surface of the inner cylinder 22. Formula (1): Y=f(x1).本發明提供一種更高效率地生成冷卻能力較高之冰之方法。 本發明之片冰製造裝置10係藉由使內筒22之壁面冷卻,使附著於經冷卻之內筒22之壁面之鹵水凍結而生成冰。噴射部13係藉由使鹵水附著於內筒22之壁面而供給鹵水。剝取部14回收於內筒22之壁面生成之冰。又,片冰製造裝置10被設計為,於將表示內筒22之壁面之每單位時間之冰之生成量之製冰速度設為Y,將內筒22之壁面之導熱率設為x1時,下式(1)成立。 Y=f(x1)・・・(1)