PURPOSE: A process for peeling the inner skin of a raw chestnut from the nut by using a chemical treatment method and physical treatment method simultaneously and apparatus thereof are provided which are allowed a raw chestnut to maintain their form and reduce the residual amount of the skin. CONSTITUTION: A process uses a chemical method such as an alkali treatment and a physical method such as passing through a brush and high pressure crusher and then washing. Thus, it comprises pretreating by dipping an outer skin-peeled raw chestnut in 0.5 to 10% caustic soda at 30 to 45°C for 40 to 60 min; removing the inner skin by allowing the pretreated chestnut to pass through a high pressure water injector (10) and a brush-attached container belt (30) in moving the chestnut to the container belt; washing by allowing sediments to pass through the high-pressure water injector; dipping the inner skin-removed raw chestnut in a water tank (40) to remove alkali; and drying.