The present study used the PROSAIL forward model to simulate vegetation canopy spectrum, introducing blue and green bands to amend the effects of atmosphere and soil background, and constructing HuanJing vegetation Index (HJVI) to avoid premature saturation. Based on ground observation data of different typical winter wheat, we established HJVI-LAI long time series inversion models and implemented different varieties cross-validation to the models. The results show that the LAI inversion model of HJVI has higher precision than similar vegetation index model, has good universality, and can be applied to remote sensing multi-temporal winter wheat growth monitoring and LAI inversion.