The present invention relates to a roll former and a method for controlling the same and, more specifically, to a method for controlling a roll former comprising: a product standard acquiring first step for a control part to acquire a standard of a first sheet which is an entering target; an entrance space controlling first step for controlling a hot-press interval of the entrance forming rolls according to a standard of the first sheet; a sheet entering first step for entering the first sheet to the roll former to form and transfer the first sheet from the entrance forming rolls in the front to the exit forming rolls in the rear; and an exit space controlling first step for controlling a hot-press interval of the exit forming rolls according to the standard of the first sheet. According to the present invention, the work efficiency can be maximized when working or converting work by providing an interval controlling timing according to the thickness of a sheet, and a method for controlling sheet entering timing when processing mixed flow and same flow sheet, and converting from mixed flow sheet to same flow sheet, or converting from same flow sheet to mixed flow sheet.