A software for extracting and pre-processing in-orbit data from a FY-3A Solar Backscatter Ultraviolet Spectrometer (SBUS) is developed. The software is mainly based on ground spectral responsivity calibration factors and some correction functions including goniometric response

nonlinearity

interrange ratios and diffuser attenuation. The principle of modified function of the software is introduced and the corresponding modified algorithm and module are established by the combination of SBUS in-orbit measuring modes and the correction principle. The modified algorithm and module are converted into an in-orbit data pre-processing software with abundant functions. The software is used to process the in-orbit spectrum measured by the solar ultraviolet spectrometer

it is then taken as an example to prove obained results. Verified experiments show that all the software functions of satellite borne SBUS have been implemented

and the similarity between the data from the solar ultraviolet spectrum and the data from SBUV/2 is within ±5%

which validates that the pre-processing software is practical.