 This research demonstrated that combining optical spectral vegetation indices, OSVIs, and radar polarimetric parameters, RPPs, can improve the accuracy of estimating leaf area index, LAI, and biomass of winter wheat. Specifically, the product of MTVI2 and DRD was found to be strongly related to LAI, while the product of MTVI2 and RVI was found to be strongly related to biomass. Additionally, the product of Osavi and DRD was found to be more accurate than the individual OSVIs or RPPs when estimating LAI and biomass. Furthermore, partial least squares regression, PLSR, was found to be more accurate than multiple stepwise regression, MSR. This article was authored by Sholian Jean, Gui Junyang, Qingang Su, and others.