Improving soil health is among the issues which have received great attention in recent decades due to population growth, urban and industrial development and the overdose use of fertilizers and pesticides. This study was carried out in order to environmentally evaluate the total concentration of selected heavy metals including lead, zinc, manganese, cobalt, chromium, copper, and nickel and affecting parameters in selected areas of Sari, Neka and Behshahr with an area of 2900 km 2 . A total 129 composite surface soil samples were taken from the depth of 0-15 cm using a random sampling within blocks scheme. Information of all the sampling sites as well as their locations were record using a GPS. Major land uses in the study region included urban, agricultural, and forest areas with 11, 66, and 52 subsamples, respectively. To investigate the vertical distribution of heavy metals and the influence of lithogenic and pedogenic processes on controlling heavy metals contents in soil, 8 soil profiles were studied on dominant soil parent materials. After preparation of soil samples, their heavy metals were extraced using 6N nitric acid solution and the concentration of selected heavy metals was determined using an atomic absorption spectrometer. Besides, selected physical and chemical soil properties including EC, pH, organic matter, calcium carbonate equivalent, and texture were measured. The spatial variability of heavy metals was studied using semivariogram models and krigging interpolation techniques. Also, the magnetic susceptibility of all the soil samples was determined and used as supplementary data to evaluate the concentration of heavy metals in soil. The results indicated that the concentration of Zn, Cu, and Pb in urban areas, agricultural area of Miandoroud plain and areas surrounding the main roads was much higher than that in other areas of the study region. This indicates the influence of human activities in such areas. The spatial variability of Mn and, to some degree, that of Co show that these elements are mostly influenced by lithogenic and pedogenic parameters. Based on the spatial distribution of the concentration of Ni and Cr in agricultural, urban and forest areas, it seems that two heavy metals are largely controlled by both anthropogenic and parent materials factors. This was further confirmed by the PCA analysis as well as the correlations of heavy metals with soil physico-chemical properties and also with magnetic susceptibility. The geometric mean concentration of selected heavy metals in forest soils were considered as natural background concentration and that in agricultural and urban areas as anthropogenic background concentration. The comparison of means indicated that the natural background concentration of Pb, Zn and Cu was statistically different from the anthropogenic background concentration of these elements at 5% level. The natural background concentration of Mn was also statistically different from its anthropogenic one. In contrast, there was no statistically significant difference betwee the natural and anthropogenic background concentrations of Cr, Co, and Ni. The results obtained were in line with those of the spatial variation and the PCA. The vertical distribution of heavy metals indicated that the concentration of heavy metals changed based on the type of parent materials, the level of soil development, and the land use of soil profile. Changes of heavy metals concentration with depth could be well explained by anthropogenic, lithogenic, pedogenic, and phytogenic processes. To environmentally assess the level of heavy metals in different areas, 2 indices of contamination factor (CF) and pollution load index (PLI) were employed. Based on the results of contamination factor, most soils studied are categorized as low to moderately contaminated and only 1.5% of the soil samples fall into the highly contaminated ltr" Keywords : Heavy metals, Soil pollution, Spatial variation, Krigging, Parent materials, Anthropogenic influence