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)?.
