Abstract: This paper introduces the characteristics, composition, testing principle, and advantages of an automatic testing system for AC permanent magnet synchronous servo motors (PMSMs) developed using LabVIEW. Compared with ordinary benchtop instruments and manual testing, this system improves testing speed and has good scalability. Keywords: Virtual instrument, data acquisition, inductance 1. Introduction From research and development to production, operation, and maintenance, servo motors require a series of tests at each stage to obtain various physical parameters and performance indicators. In the traditional testing process of permanent magnet synchronous servo motors (PMSMs), a large amount of test data such as voltage, current, power, speed, and torque needs to be collected and displayed using various testing instruments such as voltmeters, ammeters, and wattmeters. Experimenters obtain test data through these instruments. The test system is complex, uses many instruments, and the required accuracy is difficult to achieve. Therefore, establishing a high-precision, highly automated testing method is crucial. LabVIEW, short for Laboratory Virtual Instrument Engineering Workbench, provides a powerful mathematical analysis library that meets the needs of various numerical calculations and analyses in synchronous motor testing, making testing and measurement tasks simple and easy. For details, please click to download: Application of LabVIEW in the Testing of Permanent Magnet Synchronous Servo Motors.