As an industrial mother machine, CNC machine tools continue to iterate and improve in structural design and functional optimization, and the five-axis linkage technology of CNC machine tools is becoming more mature. RTCP accuracy, as the core accuracy indicator of high-end CNC machine tools, directly affects the processing quality of CNC machine tools. This article proposes an automatic RTCP accuracy detection method for CNC machine tools, which includes distance detection from the swing angle rotation center to the spindle end face and RTCP accuracy detection. The detection results will automatically generate error reports for rapid evaluation of the machining performance of CNC machine tools. Automated precision testing can replace traditional manual testing methods, improve the degree of automation application of CNC machine tools, and demonstrate the enormous value and application prospects of in-depth promotion of RTCP precision automatic testing technology for CNC machine tools.