PURPOSE: To enable the manufacture of molded windings without a mold by winding fibrous material being applied impregnation resin on the predetermined part around a winding core subjected to a mold-release treatment on the surface and winding an electric wire around the periphery of said fibrous material and further the similar fibrous material around that.

CONSTITUTION: A winding core 1 is attached to a winding machine. Next, a fibrous material 2 is wound around the winding core 1. In this case, impregnation resin is applied for a few turns from the winding core so as to form a tight laminar insulation 2'. After winding the predetermined turns, a primary winding 3 is wound. After a secondary winding 4 is similarly wound, a fiburous material 2 is wound and the impregnation resin is applied only for the several turns of ending so as to form a tight insulating layer 2'. Next, a metrallic plate 5 subjected to a mold-release treatment is wound on the periphery of said layer 2' and it is fixed by a band tape 6. Next, this is placed on a soft rubber-form sheet 7 and a ring-shaped plate 8 and the resin is impregnated into the windings and the fiburous material in a vacuum. Next, this is cured by heating and is disassembled thereby completing a molded winding. By this manufacturing method, the molded windings having good crack-resistance can be obtained without using a mold.