Traditional ATS (automatic test systems) are generally developed for instrumentation, which is less versatile and less reusable. Therefore, designing a reasonable, reliable, and efficient method of instrument and path allocation is a necessary part of improving the versatility of ATS (automatic test system). In order to solve the problem of channel selection and universality between UUT (Unit Under Test) and test instruments, firstly, UUT, instruments, test stations, etc. are described according to the IEEE1671 standard in the ATML (Automatic Test Markup Language) standard family; then, Through the matching of the UUT's demand signal and the instrument's capability signal, an instrument and path allocation algorithm is designed; finally, the algorithm is verified by an example of an airborne device, and the results show that the algorithm can effectively complete the instrument matching and allocate appropriate path to verify the feasibility and generality of the method.