The invention discloses a method suitable for a cycloid high-speed milling machining path. The method includes the steps of firstly inputting part model information and part characteristic information, and automatically dividing a machined area to obtain a key cycloid machined area and a traditional cycloid machined area; according to boundary information of the key area, calculating a cycloid center path, carrying out dispersing, and iteratively calculating the cycloid single-cycle maximum radial depth of each discrete point with the simplex method; then, screening the discrete points of the variable-radius cycloid center axis according to the maximum radial cutting-in depth; after screening is completed, calculating the cycloid machining path of the key area according to a mathematic model of a variable-radius cycloid, and carrying out dispersing on cutter location points; finally, machining left areas with a traditional machining method. By means of the method, the cycloid path is short, the time for passing through an idle-cutting path is short, and the redundancy is low; the cutter contact angle and the radial cutting-in depth can be kept relatively stable, the problems that in the high-speed milling process, the cutter contact angle is prone to sudden change, and the idle-cutting path is long are solved, the machining path is stable, and the milling efficiency is improved.