The subtropical low hill areas have the largest tea fields in China. Research on soil fertility is fundamental for accurate information management of the tea cultivations. A comprehensive evaluation of the soil fertility in Mengding Mountain was carried out with Geostatistics, GIS, and statistics methods. The study shows: (1) The soil fertility quality of Mengding Mountain is changing dramatically with the change of altitude. The hill can also be divided into different sections delimited by their fertility level: the richest soils are located in the middle and top section of the hill; the poorest, at the bottom. In other words: the higher the elevation, the richer the soil; the lower the elevation the poorer the soil. (2) The overall fertility level in Mengding Mountain is not high. There is a difference between today’s Mengding fertility quality situation and the soil quality standards of good tea fields.In fact, most of Mengding Mountain has a low-grade quality soil. Indeed, the fourth and fifth grade soils cover 42.35％ of the whole area. In contrast, the highest-grade soil accounts for less than 10％.(3) The application of this comprehensive method provides accurate and objective information on the soil fertility quality. It also gives a new practical approach to Geostatistics.