Abstract: Spindle at high speed, high speed spindle bearing inner and outer ring friction produces a large amount of heat, the heat make main shaft axial and space attitude change, produce thermal elongation, tilt and hot drift, such as deformation, the deformation and the cutting tool and workpiece relative position changes, deterioration in workpiece machining accuracy. The five measuring method to measure these variables are investigated, generate the spindle temperature rise and thermal deformation error curve, then according to the error curve executable C language compiled nc system thermal compensation program or PMC thermal compensation, numerical control system according to the temperature changing automatically update the external mechanical origin offset, correct the tool and the workpiece position deviation, can effectively reduce the spindle error caused by the thermal deformation, improve the workpiece machining accuracy.