To provide a rotor structure of a permanent magnet rotating electrical machine which effectively absorbs and relaxes thermal stress in a working temperature range, from a high-temperature side to a low-temperature side by making use of physical properties of an adhesive well, when structural adhesion through the active use of an adhesive takes place, between a cylindrical type permanent magnet made from a (NdFeB)-sintered magnet and the shaft of an iron material system.

In a rotor of the permanent magnet rotating electrical machine, constituted by fitting the cylindrical type permanent magnet made from the NdFeB-sintered magnet to an external periphery of a rotating shaft and performing the structural adhesion by applying the adhesive on the fitting surfaces, the adhesive of a sea-island structure obtained by blending a polymer type adhesive of a high elastic modulus with a polymer-based adhesive of a low elastic modulus having rubber elasticity is used as the adhesive. More specifically, it is an epoxy-silicone rubber mixture type adhesive which is formed the sea-island structure, by making silicone rubber component disperse in an epoxy-based component, and is prepared, by adapting its glass transition temperature to a substantially intermediate temperature in a motor use temperature range or a lower temperature.