A cool air exhaling apparatus in an enforced circulation type refrigerator and a control method thereof having a simple configuration so as to reduce manufacturing costs and to improve productivity, as well as freezing and refrigerating efficiency of foods. The cool air exhaling apparatus in an enforced circulation type refrigerator in which a cool air cooled by an evaporator is guided to a duct by operating a cool air circulating fan and is exhaled into the refrigerator through a cool air exhaling hollow formed in a duct cover, includes at least one cool air guide formed protrusively at the front of a duct cover in a width direction of the refrigerator, having a cool air exhaling hollow in its inner sidewall, and a duct thermal insulation material in which a cool air guide hollow having a convex curved side portion connected to the inner sidewall of the cool air guide is formed in sides of the duct cover. The cool air flows desirably along the cool air guide hollow without any separation and goes down in the vertical direction at the front of the shelf so as to form an air curtain. Thus, the cool air rarely flows outside even if the door is open, when operating the cool air circulating fan.