The invention provides a universal angular milling head virtual axis numerical control programming method and relates to a milling head programming method. The method aims at solving the problem that machining can not be achieved by a machine tool through a numerical control programmed program because of the adoption of the principal axis direction which can not be achieved or defined by the machine tool in the use process of a universal angular milling head. The method specifically includes the following steps that the theoretical position of the virtual axis of the milling head is set, the theoretical deflection position of a tool is determined, a gap between a tool bit and a workpiece is calculated, tool length compensation is conducted, the program is executed, and the tool starts to work. The method is applied to a numerical control milling machine which can not achieve special angle machining, four-axis machining can be achieved by a three-axis machine tool, five-axis machining can be achieved by a four-axis machine tool, numerical control programming application problems of the universal angular milling head are solved, and the use range of the machine tool is expanded.