Abstract: The main constituents, types, origins and migration characteristics of DNAPLs (dense non-Aqueous phase liquids) were summarized. By introducing the characteristics of spatial distribution, phase partitioning and fate of DNAPLs at contaminated sites, the migration characteristics of DNAPLs were revealed. The advances of the latest investigation technologies of DNAPLs contaminants were reviewed. The principles for determining the presence of DNAPLs and the latest technologies for detecting the distribution of DNAPLs were introduced to offer a reference for determining the proper investigation method for DNAPLs sites, which would benefit a more precise scoping of DNAPLs distribution, as well as the development of cost-effective remedial plans.