A new wavelength calibration method for the solar backscattered ultraviolet spectroradiometer (SBUS) was described. The characteristic lines with continuous spectrum plus monochromator were selected to overcome the deletion of discrete lines in special wavelength bands. The calibration light source system for the SBUS is made up of the high stable xenon lamp, the pre- and post- optical systems together with the 1.5 meters Czerny-Turner monochromator. The basic principle of the new method is the procedure of inter-calibration. The calibration light source system reference wavelengths is given by the SBUS’s mercury lamp in the ultraviolet band, which in turn provides the 12 characteristic wavelengths of ozone with a better linearity for SBUS. The calibrated results satisfy the demands of the wavelength accuracy and the spectral band precision for ozone retrieval.