The present invention discloses a numerical control cutting cutter path data denoising method. A series of cutter path data of cutter operation locus in a numerical control cutting process is employed to compare with the state changing conditions of cutter path geometric coordinate data of state conversion and state maintenance in a cutter finite state machine, the cutter path data generated when a cutter is operated in a cutting state is extracted, and the cutter path noise data of the cutter generated in the operation states in the processes such as idle running, idle movement, plunge cut process, cutter lifting process and the like is filtered so as to realize the numerical control cutting cutter path data denoising. The numerical control cutting cutter path data denoising method employs the cutter data denoising method and technology of the cutter finite state machine to theoretically ensure the 100% denoising rate; the workpiece processing quality risk is reduced and the generation of inferior-quality products is reduced while the denoising requirement is satisfied; and software can be employed to perform preprocessing of the numerical control cutting cutter path data to realize real-time denoising of the cutter path data, and data excavation and data analysis are employed to realize a fault early warning function and the like so as to improve the workpiece processing efficiency.