In order to improve the machining accuracy of the cam profile surface and reduce the influence of tool errors on the normal error of the cam profile during the machining process, by analyzing the structural characteristics of the cam profile indexing cam and the existing problems in the machining method, and reducing the extreme difference between the actual profile and the theoretical profile obtained by processing, the principle of multiple envelopes for one-side processing was proposed, The effectiveness of the method was demonstrated and a simulation calculation was carried out. The theoretical research was based on the cam profile equation of the arc surface indexing of the set coordinate system, using spatial meshing principle and rotation transformation matrix, according to the principle of one-side machining and multiple envelopes, the actual contour equation after the machining of the globular indexing cam was deduced and calculated, the tool position compensation and tool control method of one-side machining multiple envelope principle was researched. The problem of tool position control based on the principle of multiple envelopes for one-side machining of a globular indexing cam was solved. Matlab simulation results showed that the method can significantly reduce the normal error of the cam profile surface and improve the machining accuracy of the cam, and it had important practical application value.