The Solar spectral irradiance monitor (SSIM) is China's first spaceborne solar irradiance spectrometer designed to measure solar continuum spectrumat the top of the atmosphere. It is mounted on the Fengyun-3E (FY-3E) satellite, the fifth satellite in the second generation of Chinese polar-orbit meteorological satellites. SSIM covers a spectral range from 165 to 2 400 nm, with a spectral resolution of 1 nm and sampling intervals of 0.1 and 0.25 nm in the ultraviolet and visible bands, which can capture fine solar spectrum characteristics of the sun. This study evaluated the spectral calibration accuracy of the SSIM visible band using the latest Total and Spectral Solar Irradiance Sensor-1 Hybrid Solar Reference Spectrum (TSIS-1 HSRS) as reference, with measurements from September 2021 to November 2023. By convoluting the pre-launch spectral slit function with TSIS-1 HSRS, a reference spectrum was generated to match the SSIM's characteristics. Using the spectrum matching method, nine solar Fraunhofer lines were selected to characterize wavelength shifts. The temporalvariationof spectral drift was analyzed, and a refined correction method was developed to improvethe spectral calibration accuracy of SSIM. Considering the characteristics of the early morning orbit, the annual variation of the Doppler shift was first analyzed, revealing the maximum wavelength shift of -0.005 to 0.001nm at 700 nm. Based on the assessment results of the Fraunhofer lines, the long-term variation of wavelength shifts in the visible band exhibited periodic fluctuations, with the shift of 410 nm varying from -0.032 to 0.025 nm compared to the initial on-orbit state. Further analysis indicates that the spectral driftis strongly correlated with the periodic fluctuations in the grating temperature of SSIM, with correlation coefficients between the wavelength shifts of the Fraunhofer lines and the grating temperature ranging from -0.766 to -0.964. Considering the drift characteristics on different spectral regions, the method of segmenting and sliding to calculate wavelength shifts and then fitting them for correction has been applied to the SSIM visible band, which shows that the results of spectral calibration accuracy are better than 0.028 nm. This method eliminates the impact of satellite launch, environmental changes on spectral accuracy, and also temperature fluctuations induced spectral drift. It has good long-term stability and effectively improves the on-orbit spectral calibration accuracy of SSIM. This paper provides a reference for the research on the on-orbit spectral calibration of wide-band solar spectrometers.