In practice,due to fiber birefringence and input polarization,the phase shift often occurs in distributed optical fiber oil and gas pipeline security monitoring and early warning system based on dual Mach-Zehnder fiber interferometers.It also causes the degradation of two detection signals for alarm location and the gross locating error.A new type of Simulated Annealing（SA） method based on dual Mach-Zehnder signal correlation coefficient is proposed for real-time control of input polarization in this paper，which can keep the signals′ correlation coefficient stable.When the detection signals′ correlation degenerates,the input polarization can be changed through the feedback control to recover a steady signal correlation.Field test results show that the Simulated Annealing Algorithm based on dual Mach-Zehnder signal correlation coefficient can make a fast search for the optimal state of polarization,and maintain a steady signal correlation.Compared with the situation without the polarization control,the system′s stability is significantly improved.