Abstract: Aiming at the problem of poor anti-interference of temperature monitoring in professional warehouse of intelligent power supply station, a high-precision three-dimensional space correction method is proposed, which is suitable for temperature monitoring array with weak reflection grating. The three-dimensional spatial data of the three interference signals output by the 3×3 coupler is constructed, and the space matrix transformation is obtained by coordinate rotation and least square method, and further solved by space mapping matrix. Finally, the DC component and AC component coefficients of the three signals are calculated, and the high-precision interference signals are output by coefficient correction. The simulation results show that the proposed method can effectively calculate the DC and AC component coefficients of the three-way signal, and has more advantages than the traditional two-dimensional ellipse fitting results. The Pearson correlation coefficient R² can reach more than 0.999 703 4. The proposed algorithm is used to carry out repeated experiments, calculate the DC and AC component coefficients of interference signals, and obtain stable results with standard deviation less than 0.006, which proves the effectiveness of the method for temperature monitoring, and has a certain engineering application prospect for future event classification and subsequent processing.