Abstract: In order to realize the laser quenching heat treatment of cams,according to three preconditions for getting uniform hardened layer,combining with movement forms of laser processing machines,the mathematical models of relative movement were established about laser beam and the cam surface in the laser quenching process,the theoretic analysis and algorithm research were carried out for the laser head's movement,and the formulas of X,ω,B three-axis motion were derived. The result shows that the laser quenching heat treatment of the cam can be controlled feasibly,and it lays a theoretical foundation for the process of complex parts.