Abstract: The optimum design of a high speed bevel gear has been accomplished. Atfirst, the sensitivity matrix of natural frequencies of the bevel gear is obtained in relation to desge variables. And then the optimum peruturbation on aeration procedure is applied to the dynamie optim design of a high speed bevel gear. Some resulls satisfying frequencies cunstrsunts are ootaned. The result with smallest weight is selected. And me effect of proess accuraey on natural freqaencies the bevel gear are discussed. The results of the experiments on the bevel gear manufactured sa the the optimum oesign. s a success.