[Objective] The aim of this study was to explore the spatial distribution characteristics and the regularity of available silicon in the soil of Dongting Lake, and to provide scientific basis and practical guidance for the development of precision agriculture in the Dongting Lake area and the maintenance of farmland.[Methods] The geo-statistics and GIS technology were both used.[Results] There was a significantly positive correlation between the content of available silicon in the Dongting Lake area and the yield of rice. Silicon is an important nutrient element for rice growth. The average available silicon content in the paddy field around Dongting Lake was 155.1 mg/kg. Though in most cases, it varied from 100 to 200 mg/kg, the margin difference was so great as to the highest content was 27 times of the lowest. Spatially, the content of the part was found higher than the values of periphery, and in the northwest part it had the lowest silicon. Soil available silicon has a strong spatial correlation, and its spatial variation is mainly affected by soil type, soil pH value, soil parent material and other factors.[Conclusion] Silicon plays an important role in rice growth and development. Because soil types in natural geographical environment is not the same, so soil available silicon content normally varies. The abundance of soil available silicon is affected mainly by soil parent material and has significant positive correlation with soil pH value.