Design problems of permanent magnet (PM) high-speed machines have some peculiarities. The possibilities of increasing the electromagnetic torque are depended on mechanical, electrical and magnetic aspects. Mechanical aspects of designing for some types of high speed PM electrical machines such as PM synchronous machines with a wide range of rotating speed and power rating are specially discussed in the paper. The analysis technique for machines of such type is developed. Numerical solution results for different ranges of PM machines and testing results for two realized designs are presented and discussed.