Abstract: In order to solve the problem of inconsistent spectral wavenumbers between slave and host of near infrared spectrometers, spectra were treated by five interpolation models: Zero, Slinear, Quadratic, Cubic and Nearest. A new smooth interpolation method based on Savitzky-Golay (SG-Inter) was proposed to make the wavenumbers of the slave spectra consistent with those of the host spectra after interpolation, and the transfer failure of the host model caused by inconsistent spectral wavenumbers was effectively avoided. The results showed that the spectra processed with the SG-Inter interpolation had a higher consistency degree with the original spectra, the RMSEs (Root mean square errors) of indexes predicted by the model after transfer were the lowest. This method synchronized the calculation of spectrum smooth pre-processing and interpolation transformation, which simplified the workflow of model transfer and effectively improved the general adaptability of the host model.