The urban soils are affected greatly by human activity and characterized by significantly anthropogenic enhancement of heavy metals.It will be helpful for us to protect and to remedy the ecosystem of urban soils better if we are learn the relation between the abundance and the form of heavy metals in soil with the physical and chemical properties of soils and the factors of surrounding environment.This study was conducted to examine the content and the forms of heavy metals in urban soils in Nanjing, applying the theory of grey system to analyze the factors influencing the pollution of heavy metals.Such factors as soil organic matter content, soil clay content, soil pH, the distance from industrial zone, the automobile flow, and the fraction of residue in soils were concerned in this paper.Grey-relational analysis showed that the most important factor is the distance from industrial zone.The factors such as soil clay content and soil pH are also important.Other factors are relatively unimportant.