Abstract: With the principles of forest ecology and geology as well as remote sensing science, the forest sites in Yuntaishan mountain area, jiangsu province, were divided into 13 site types through the method of quantitative theory Ⅱ. The mean estimated rate was 94.95%. Furthermore, the site quality of each type was evaluated also with fuzzy theory. With the very-fying of field investigation data the results of classification and evaluation were suitable. Classification precision was about 63.39%. And also the evaluation value of each site type was calculated. The classification and evaluation technologies on forest sites with remote sensing technology were also given in the paper.