The　profile　error　of　a　globoidal　cam　resulting　from　motion　errors　of　two　coordinated　rotational　axes　of　a　machine　tool　in　machining　is　studied.　A　novel　method　of　solving　profile　error　is　presented.　According　to　this　method,　the　minimum　distance　from　a　point　on　the　profile　actually　machined　to　the　desired　profile　is　referred　to　as　the　profile　error.　Then,　the　mathematic　model　of　profile　error　resulting　from　the　motion　errors　of　the　machine　tool　is　built.　After　that,　the　type　TC40　globoidal　cam　is　employed　as　an　example　to　analyze　the　machining　error.　The　linear　influence　coefficients　of　the　motion　errors　of　the　two　coordinated　rotational　axes　on　the　profile　error　are　determined.　The　maximum　value　of　the　machining　errors　resulting　from　the　motion　errors　of　the　two　rotational　axes　of　machine　tool　is　yielded.　A　novel　method　of　improving　the　velocity　of　solving　the　maximum　value　by　using　the　linear　influence　coefficient　is　presented.　At　last,　an　isogram　is　introduced　to　analyze　the　influence　of　the　motion　errors　of　the　two　coordinated　rotational　axes　of　the　machine　tool　on　the　globoidal　cam　profile　error.　©　(2012)　Trans　Tech　Publications,　Switzerland.