The low temperature superconducting nanowire single-photon detectors have become a key infrared photon counting technology in communication and astronomy applications. However, the constrained physical space of devices demands for high-performance superconducting detectors capable of operation at higher temperature. To date, the fabrication of high temperature superconductor nanowires is still facing seriously uneven lateral damage during ion etching process. In this work, we report a promising fabricating method for high-temperature superconducting YBa2Cu3O7−x (YBCO) nanowires, using a focused helium ion beam to minimize the lateral damage of the cut. Based on the simulation, we designed tangent circles and adjacent isosceles triangles to replace lines in cutting nanowires for reducing the superimposed damage of He+ ions. The lateral damage of single helium ion cut has been reduced with a superimposed damage width decrease from 58.8 nm to 29.7 nm. This work provides a platform for boosting the YBCO nanowires to achieve single photon detection.