Contents and distribution of soil pH, total potassium (TK), total nitrogen (TN), total phosphorus (TP), organic matter (OM) and available phosphorus (AP) across Nanjing urban area were studied using GIS technology and geostatistical analysis methods. Semivariograms for soil pH, total potassium (TK) were well fitted by linear with sill model, and could be further interpolated by block-Kriging, while no suitable model fitted the semivariograms for TP, AP, OM and TN, even after logarithm conversion of these properties. It was suggested that the spatial variability of pH and TK was primarily controlled by the structural factors of the spatial heterogeneity of parent material and landform, whereas variability of TP, AP, OM and TN was greatly affected by urban human activities and they were spatially heterogeneous even in a short distance.