The evaluation of soil fertility in Zhuxi watershed was studied based on the methods of Geostatistics and GIS. The results showed that the higher soil fertility area was distributed on farmland in the downstream, the lowest soil fertility area was distributed in the central part of the watershed where soil was eroded seriously. The overall of soil fertility was low, the percentage of area was less than 10% in grade 1 and grade 2 which fertility were better, the area of grade 4 taken more than 50%, the area of grade 5 which fertility was lowest still more than 20%. It was indicated that although soil erosion was controlled for years in this watershed, soil fertility was still poor, restoration was a long-term process. The evaluation of soil fertility based on Geostatistics and GIS, which demonstrated that the soil fertility rapidly and intuitive, and give practical application for the results of Geostatistics.