Since　the　profile　of　the　globoidal　indexing　cam　is　a　complex　spiral　surface,　the　cam　mechanism　motion　accuracy　is　influenced　by　the　processing　quality　of　the　profile.　Based　on　the　principle　of　differential　geometry　and　the　theory　of　characteristics,　inspection　method　using　a　universal　coordinate　measuring　machine　(CMM)　was　described　in　this　paper.　Firstly,　according　to　the　required　motion　and　geometry　of　follower,　the　mathematical　model　of　cam　profile　was　established　by　using　the　theory　of　envelopes　for　a　one-parameter　family　of　surfaces.　Secondly,　sampling　strategy,　which　is　the　moving　point　matrix　of　the　probe,　was　determined.　Thirdly,　the　geometrical　errors　of　the　cam　profile　were　evaluated　according　to　the　data　acquired.　Software,　which　was　used　on　CMM,　was　developed　to　fulfill　this　measuring　task.　The　precision　measurement　and　deviation　assessment　of　the　globoidal　indexing　cam＇s　profile　were　achieved.