A study was carried out using Geostatistics and Geographical Information System(GIS) technologies to explore spatial variability of soil organic carbon content in different soil layers (0~20, 20~40, 40~60, 60~80, 80~100, 0~100 cm) in Cixi City, on the south coast of the Hangzhou Bay. Results show that the average contents of soil organic carbon in the soil layers varied from 3.49 g kg^-1 to 7.95 g kg^-1 in the study area, with variation coefficients ranging from 54.51% to 67.34%, indicating a moderate degree of variability. Geostatistical analysis reveals that the value of nugget effect varied from 0.141 to 0.372, displaying strong spatial correlation, and that the optimal semi-variance models for the soil layers from the surface down to the bottom of a soil profile were Gaussian, exponential, exponential, Gaussian and spherical model respectively; The results of Kriging demonstrate that soil organic carbon displayed an increasing trend from beach to inland in all the soil layers, and a decreasing trend with soil depth in a soil profile, and was distributed in the surface soil layer (0~20 cm) like a band in parallel with the coastline. Both different land use patterns and different reclamation history intensified spatial variability of soil organic carbon. All the findings indicating that the spatial variability of soil organic carbon is mainly caused by structural factors in Cixi City, may provide soil organic matter reference to the study to understand characteristics of the distribution of organic carbon in soils on the south coast of the Hangzhou Bay.