To solve the camshaft’s deformation compressed by the continuous and variable force when grinding, the influence of grinding force on the cams curve accuracy was analyzed. The axial deformation and radial deformation were decoupled. The deformation value solution equation in variable position and angle was deduced. The interpolation principle of the CNC (computer numerical control) camshaft grinder was analyzed. The X-C linkage kinematics equation which included deformation errors, workpiece rotation axis, and grinding wheel axis was built. The soft error compensation manner by adding the errors to the interpolation value was proposed. The deformation error of one intake-exhaust camshaft was modeled and simulated. The CNC camshaft grinder was compensated and the manufacturing test was executed. The simulation and manufacturing result showed that camshafts contours accuracy was improved 5μm by the deformation compensation.