PURPOSE: To make it possible to obtain a superconductive magnet capable of generating a stable magnetic field as well as compact, by providing a reinforced plastic layer on the outer periphery of the inner coil, and installing a coil using this layer as a part of a bobbin therefor.

CONSTITUTION: A bobbin 9 made from glass epoxy is wound with a stabilized superconductive wire insulated with formal to form a main coil 10. The whole surface of the outer periphery of the coil 10 is wound with about four turns of a glass cloth, and the coil 10 is secured to a predetermined position by means of a half cylinder 12 made of glass epoxy. The half cylinder 12 constitutes a part of the bobbin 9. In addition, the half cylinder 12 secures the coil 10 through the glass cloth so that a slight gap 13 is formed. The portion of the glass cloth not covered with the half cylinder 12 is wound with a TETRON tape and vacuum-impregnated with epoxy resin to secure the bobbin 9, the main coil 10 and the half cylinder 12 in a unitary body. Then, the outer periphery of the glass epoxy resin layer 11 and the end surfaces of the half cylinder 12 are cut and wound with the above-mentioned wire to form subcoils 14, 15, thereby obtaining a superconductive magnet capable of generating a stable magnetic field as well as compact.