Heavy metals such as lead, zinc, copper, arsenic, and cadmium are usually found in surface soils affected by mining or smelting activities, agricultural practices, and industrial areas. The total amount of trace metals in soils is generally not sufficient to assess the environmental impacts of metal contamination. Therefore, chemical forms and binding types of metals enable evaluation of their behavior and bioavailability in the soil environment. Thirty-two soil samples were analyzed, determining the chemical fractionation of As, Pb and Cd using by the six-step sequential extraction (SEP), X-ray absorption fine structure (XAFS), X-ray diffractometer (XRD) and scanning electron microscopy. The results of SEP showed that most of the Pb were associated with non-residual fractions, mainly in crystalline (hydrous) iron oxides (goethite). The Cd appeared mainly associated with adsorbed fraction in the roots of the dried plants in the soils. The XAFS spectra of the samples showed that Pb in the soil is adsorption form into Fe-(hydr)oxides surface. Results of XAFS analysis showed Cd in the samples were adsorbed on clay minerals. Arsenic appeared mainly associated with the amorphous and crystalline iron oxides. Heavy metals are associated with adsorbed fraction, amorphous and crystalline iron oxides, thus being potentially more mobile to the environment if conditions were more acidic or reducing. Keywords: Heavy metals, soil, chemical speciation, sequential extraction