Spatially modulated imaging Fourier transform spectrometer (SMIFTS) is an instrument that depended on interference,it can obtain interferential information and achieve spectral information by Fourier transform. The lamp-house of outdoor calibration is sun,which can offset effective lamp-house of laboratory calibration (sun simulation)′s disadvantage of low shortwave radiation and signal to noise ratio (SNR),also simulate sun reflection spectrum speciality availably of SMIFTS object,obtained interferential information exactly,result of laboratory radiation calibration is validated. Principle,method and result of the experiment are shown,used sun-aerosphere-diffuse reflection method and standard-radiation-transfer method to accomplish outfield calibration in Dali. The results indicated that the uncertainty of sun-aerosphere-diffuse reflection method is 6.3%,uncertainty of sun-aerosphere-diffuse reflection method is 6.0%.