One aspect of the present invention provides a method of manufacturing a circuit board. The method comprising: preparing a first substrate member in which a cavity is formed, the cavity being defined at least in part by a pair of wall surfaces facing each other in a lateral direction and opens upward in an up-down direction perpendicular to the lateral direction; preparing a magnetic member having a plurality of magnetic pieces which are coupled with each other by at least one positioning member so as to be arranged at regular intervals in a predetermined direction; placing the magnetic member in the cavity so that the predetermined direction coincides with the lateral direction or a front-rear direction perpendicular to both of the lateral direction and the up-down direction; and closing the cavity by placing a second substrate member on the first substrate member.

Another aspect of the present invention provides a circuit board which comprises a first substrate member, a magnetic member and a second substrate member. The first substrate member is formed with a cavity corresponding to the magnetic member. The cavity is defined at least in part by a pair of wall surfaces facing each other in a lateral direction and opens upward in an up-down direction perpendicular to the lateral direction. The magnetic member has a plurality of magnetic pieces. The magnetic pieces are placed in the cavity and arranged at regular intervals along the lateral direction or a front-rear direction perpendicular to both of the lateral direction and the up-down direction. The second substrate member is placed on the first substrate member to close the cavity.