A cylindrical magnetic circuit which is able to prevent deformation of a cylindrical yoke for holding two or more magnets without increasing the thickness of the yoke more than required, and a method of producing such a circuit. A cylindrical magnetic circuit (1) for generating a magnetic field in a space inside of plural annularly placed magnets (2), including: a cylindrical yoke (3) which is placed radially outside the magnets (2) and is fixed to the magnets directly or via an intermediate member or substance; and at least one nonmagnetic member 4 existing between pairs of circumferentially adjacent magnets, and a method for producing the cylindrical magnetic circuit (1).