By using a perpendicular magnetization mode to the surface of a recording medium, a new recording system that has extremely high volume density will be realized. Its minimum bit-length corresponds to the crystalline particle size which is about one-tenth the thickness of a perpendicular magnetic anisotropy film used for recording media. For writing and reading, a single pole type magnetic head made of a soft magnetic thin film has been also proposed. In this paper, the principles, methods and feasibilities of perpendicular magnetic recording are described.