Abstract: In this paper, the influence of numerical control machine tool axis motion error, tool error, tooling and other original errors on the accuracy of numerical control processing for double-enveloping toroid worm gear drives is studied by using the theory of multi-body system modeling and spatial meshing principle as the foundation. The surface equation with above various errors of planar double-enveloping toroid worm gear drive is deduced, and error analysis is conducted using Newton iterative method.The influence of the error on the machining precision of worm profile surface is theoretically elaborated, which provides theoretical reference for NC machining of double-enveloping toroid worm gear drives with high precision.