The application of fully polarimetric SAR images in the post-earthquake disaster area to quickly extract seismic damage information of buildings and estimate the seismic damage level can provide important disaster information for the support of the rapid and effective implementation of emergency rescue. Based on the polarization scattering mechanism,we establishe the Pauli-Wishart supervised polarimetric classification based on polarization scattering matrix to extract seismic damage information of buildings and estimate seismic damage level on a street block scale,including Pauli decomposition,Wishart supervised classification and remote sensing seismic index. Taking the full polarimetric Radarsat-2 images after the Yushu M_S7.1 earthquake on April 14,2010 in Qinghai,China as an example dataset,we extracted the seismic damage information of buildings. Through statistical analysis,we determined that the overall classification accuracy of the results reaches 0.81,with the Kappa value of 0.61,indicating that the method of extracting seismic damage of buildings in this paper is effective and feasible.