A method of manufacturing a magnetic disk is provided. The method of manufacturing a magnetic disk includes the step of disposing a plurality of magnetic recording tracks concentrically, each of the magnetic recording track including a data information recording area and a control information recording area, and the step of forming a separation groove between data areas each included in the data information recording area, and in which data is written, wherein, the step of forming a separation groove includes the step of forming a resist layer having an opening corresponding to a pattern of the separation groove by photolithography, and the step of etching to form the separation groove on a surface of a substrate or a material formed on the substrate through the opening of the resist layer, the step of forming the resist layer and the step of etching are performed for both of a front surface and a back surface of the substrate.