This study aims to evaluate and compare heavy metal contamination in soils of Chadegan County (Isfahan Province) and Aligudarz County (Lorestan Province), both located within the Sanandaj-Sirjan structural zone. A total of 128 soil samples from Chadegan and 100 from Aligudarz were collected at 30 cm depth and analyzed by ICP-MS. Geochemical indices including the geo-accumulation index (Igeo), contamination factor (Cf), pollution load index (PLI), and enrichment factor (EF) were calculated using world average shale as background reference. Statistical analyses comprised Pearson correlation, cluster analysis, and spatial interpolation by ordinary kriging in ArcGIS. Results indicate that in Chadegan, PLI values for all elements remain below one, reflecting low to moderate contamination levels. In contrast, Aligudarz shows significant contamination in five elements: nickel (PLI=6.04), chromium (PLI=4.45), scandium (PLI=4.37), cobalt (PLI=3.33), and lead (PLI=2.36). Chromium recorded the highest concentrations in both areas (Chadegan: 184 ppm; Aligudarz: 239 ppm). The exceptionally high zinc enrichment factor in Aligudarz (EF=60.9) is attributed to the Golzard lead-zinc mine. The primary sources of contamination in Aligudarz are mining activities and hydrothermal alteration of metamorphic rocks, while in Chadegan the main anthropogenic source is a stone-crusher plant operating without an adequate filtration system. Continuous environmental monitoring and installation of pollution control equipment are recommended for both areas