In the HITRAN database, the temperature of the line is modified to the temperature, and then the synthetic calibration spectra are obtained. The synthetic calibration spectra and the spectra obtained by the experiments were performed by nonlinear least squares fitting, and thus the standard of CH4 concentrations was obtained at different temperatures. This inversion algorithm has a high accuracy at room temperature, but with the increase of temperature, the error of the concentration gradually increased. The high-temperature gas temperature correction is carried out by FTIR for the correction of high temperature spectral parameters, better synthetic calibration spectra can be obtained by using partition given temperature correction coefficient method, and combining HITRAN database.