The application of worm on CNC turntable, the principle of mechanical transmission and control, and the adjustment method of tooth side clearance were analyzed.Force calculation formulas of the worm, wheel and supporting bearings on CNC table were derived. The influences of the gear and worm transmission mechanism error and the worm gear eccentric assembly on the accuracy of CNC table were studied.The principle and method of checking the accuracy of CNC table by using laser interferometer were introduced. It provides a method for calculating the force of the worm drive mechanism and bearing of the CNC table, and provides reference for accuracy design, debugging and checking of CNC table.