Aiming at the problem of large positioning error of dual Mach-Zehnder interferometric optical fiber vibration sensor system, a vibration positioning method based on Burg algorithm is proposed. The spectral analysis method is used to compare the energy characteristics of the Burg algorithm and the fast Fourier transform algorithm at different frequencies. The optimal frequency is determined by calculating the energy ratio, and the value selection analysis of the optimal order of the Burg algorithm is carried out. Under the conditions of optimal frequency and order, feature data frames are extracted, and the time delay between two vibration signals is obtained through cross correlation calculation, so as to obtain the vibration position. In the dual Mach-Zehnder interferometric optical fiber vibration sensor system, the experimental research on vibration location is carried out. The experimental results show that the method can successfully extract the characteristic data frame of vibration signal frequency on the 2. 2 km sensing optical fiber, and the absolute error of vibration location is 7. 3 m, which provides a new method to improve the positioning accuracy of the dual Mach-Zehnder interferometric optical fiber sensing system.