This paper investigated concentrations of heavy metals in roadside surface soil samples collected from the D-100 highway in Sakarya, Turkey. The sequential extraction procedure has been applied to 24 soil sur- face samples and heavy metals concentrations (Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V, and Zn) determined by ICP-OES. The three-step BCR sequential extraction procedure was used in order to evaluate mobility, availability, and persistence of trace elements in roadside surface soil samples. Validation of the analytical results was checked by analysis of the BCR-701 certified reference material. The results showed good agree- ment between the obtained and the certified values for the heavy metals analyzed. The results show that Zn (229 µg/g), Pb (227 µg/g), Mn (129 µg/g), Fe (113 µg/g), and Cr (101 µg/g) are the most contaminated heavy metals in roadside surface soil samples.