Abstract: This article has control theory introduced into the design of machine construction, and, in accordance with the view of transforming information, has analyzed the dynamic error of the drive chain of hobbing machines, and successfully designed mechanical feed back drive mechanism for compensating drive error. The practical operation test in Y3180H bobbing machine for recent two years has proved this drive mechanism to be simple in construction, stable in operation, and excellent in effect. Hence the precision of the processed gear can be raised from class7 to class 5 The design and test of the mechanical driving system has proved that it is of great significance to take control theory into consideration while designing machine tools.