With the rapid economic development and large-scale urbanization, contaminated sites resulted from dismissed enterprises have been a serious problem in China. The reuse of these contaminated sites may pose threat to human health and local ecosystem if without contamination investigation, risk assessment and remediation. The promulgation of a series of environmental assessment guidelines and standards, including those for site environmental assessment and soil screening levels, would greatly promote the management of contaminated sites. Soil pollution was a global environmental issue and many countries and regions had developed soil screening levels or cleanup objectives. The screening of contaminants of concern (COC) was the principal point of developing soil screening levels. The experience in screening COC during establishing screening levels for soil risk assessment of contaminated sites in Beijing was introduced, which could provide reference for other cities and regions in determining COC.