The purpose of this study was to address the spatial distribution and the health risk of potentially toxic elements (Cr, Ni, Cu, Zn, As, Cd, Pb, and Hg) in different particle sizes of road dust samples from an industrial area of Pohang, South Korea. Concentrations in the six particle size fractions revealed a precise increasing order with decreasing particle size, with the highest average concentration in the [< 63 μm] particle size fraction for Zn (6161 mg/kg) and Cr (5225 mg/kg). In the [< 63 μm] particle size fraction, the mean values of the geoaccumulation index were found in the decreasing order: Zn≈Cd (5.4) > Cr (5.1) > Pb (4.1) > Cu≈Hg (3.3) > Ni (2.3) > As (0.3), and exceeded 4 in all sizes for Cr, showing a high to extremely high pollution status. It seems to be related to chromium plating and stainless alloy containing Cr in the steel industry process. Non-carcinogenic risk was found in Cr for children, while carcinogenic risk was found unacceptable for Ni, As, and Cd in children and for As and Ni in adults. The location of the study area near industrial, residential, and coastal areas makes its road dust pollution a combined threat to the human health and the marine environment. This study provides a basis for the improvement in pollution prevention and control strategies to reduce the environmental impact of potentially toxic metal contamination in road dust, as well as a road dust management insight in coastal industrial areas.