Abstract: Determining weights of heavy metal contamination is important in the soil environment quality assessment. Weights of heavy metal contamination were computed according to impacts of heavy metals on human health by using improved classical analytical hierarchy process (AHP) in the soil environment quality assessment. Aiming at the problem of soils heavy metal pollutions in Baiyin which is a resources city and a typical mining city, the author evaluated the effects of heavy metals of cultivated land by GIS and weighted mean method. The results showed that: among the 5 heavy metals, the variation degree from big to small was As, Zn, Cu, Cr, Pb. The integrated pollution index of soil heavy metals was 0.48, which meant the soil in study area was security. The correlation analysis showed extremely significant positive correlation between Pb and Zn, Pb and Cu, Zn and Cu. The space distribution of soil heavy metals pollution revealed that most of the arable layer soil in Baiyin District was at security level, only the central and southeastern parts of the region was at light pollution levels. Finally, the result of grade evaluation of the heavy metal pollution of cultivated land showed: bottom level, safety level, tarnished level, pollution level accounted for 24.83%, 70.33%, 2.72%,