In distributed Raman temperature measuring system, the temperature of the contained information of anti stokes light is weak, easily masked by noise, and the traditional denoising method is easy to filter to remove the original characteristics of the system, thus aiming at these problems, this paper USES the EEMD combined with wavelet threshold denoising method to reduce the noise of engine, under the condition of retain the original information feature, Greatly improve the system's signal to noise ratio (SNR) and temperature measurement accuracy. Simulation results show that the SNR of the algorithm is improved by 2.3 dB when the noise is 1dB. Experimental results show that the measurement accuracy of the system is improved by 76.11%. Through a separate wavelet threshold de-noising process, the temperature curve of the fusion point of the optical fiber is more than 1℃ fluctuation range, and the demodulation temperature fluctuation range of the system is about 0.5℃ after the algorithm is adopted. Finally, the experiment proves that the algorithm does not affect the spatial resolution of the system.