Abstract: As an important index of material testing machine, the coaxiality of material testing machine is related to the accuracy of material mechanical test results. At present, according to ASTM standards, the method for measuring the coaxiality of material testing machines by using the testing machine coaxiality measuring instrument with three layers of strain gauges has been widely concerned. Based on the analysis of the similarities and differences of the detection methods for coaxiality, this paper mainly introduces the detection methods for coaxiality of strain testing machine, and gives some consideration on error control and traceability methods, so as to improve the understanding of the detection methods for coaxiality of testing machines and better meet the testing requirements for coaxiality of testing machines.