For distributed optical fiber temperature measurement system, the back Raman scattering signal containing temperature information generated by it is extremely weak, so it is easy to be masked by white noise. In this paper, a joint noise reduction algorithm based on VMD-SVD is designed, and the important parameters of the algorithm are selected with better noise reduction performance indicators by comparing the noise reduction of the constructed simulation signal. Experiments show that when the joint algorithm and EMD, VMD, EMD-SVD algorithm are used to reduce the noise of multiple groups of test signals respectively, the VMD-SVD noise reduction algorithm has an improvement of more than 15 dB compared with the EMD algorithm, and more than 9 dB compared with the VMD algorithm. Finally, compared with the EMD-SVD algorithm, the VMD-SVD algorithm has an improvement of more than 1 dB. Finally, when the above algorithm is applied to reduce the noise of multiple groups of backward Raman scattering signals measured by the distributed optical fiber temperature measurement system, VMD-SVD noise reduction algorithm can also effectively eliminate the white noise of the signal, laying the foundation for subsequent high-quality temperature measurement.