According to the characteristics of supper-resolution, spatial interference and narrow bandwidth of spatial heterodyne spectrometer (SHS), the principle and requirement of calibration are analyzed, the methods of spectral calibration using tunable uniform planar radiances and the radiometric calibration with sphere are presented, the calibration systems are built, the spectral and radiometric calibrations of the spectrometer are fulfilled, and the calibration uncertainty is analyzed. The spectral calibration uncertainty is 0.015 cm-1, and the radiometric calibration uncertainty is 4.02%. The calibration uncertainty meets the given requirements. The calibration results are verified by measuring the actual atmospheric CO2 absorption spectra. The results show that the positions of the absorption peaks and the radiance brightness values fit well between the measured and the simulated spectra, which provides a foundation for quantitative inversion of CO2.