The present invention proposes a method for preparing a KTP nonlinear racetrack microring resonator, including six steps of KTP wafer processing, ion implantation, electron beam exposure, follow-up processing, ion etching processing and final processing, through one process of ion implantation, Just realized the preparation of the thin-film waveguide structure similar to the on-chip lithium niobate thin-film material, the production process is greatly simplified, the time is shortened, and the cost is significantly reduced. At the same time, the KTP nonlinear microring resonator finally prepared by the present invention is compatible with existing Compared with Lithium Oxide nonlinear microring resonators, it has a higher optical damage threshold, which can increase the output power of nonlinear frequency conversion light from microwatts to milliwatts, and is suitable for both input and output optical signals. In the case of pulsed laser, ion implantation, electron beam exposure, metal evaporation deposition coating, and reactive ion etching are all relatively mature micro-nano processing technologies, making the present invention have good operability and repeatability.