Abstract: Abstract: Through an analysis of shallow groundwater in a certain area, this paper introduces the main halogenated hydrocarbon contaminants (CHCl3, CCl4, CHCl = CCl2, CCl2 = CCl2, CHBr3) in shallow groundwater in the area, and illustrates that the main contaminants of halogenated hydrocarbons are CHCl3, CHCl = CCl2 and CCl2 = CCl2 and that the main contamination sources of halogenated hydrocarbons in shallow groundwater are large open waste areas with no defending measures, sewage rivers and ditches and special industrial enterprises, and confirms that the two main factors for the contamination of halogenated hydrocarbons are the distribution of contamination sources and the lithology of the aeration zone and that the high-concentration regions of halogenated hydrocarbons are the top of the alluvial-diluvial fan and the transitional zone between phreatic water and confined water. This paper also preliminarily explores the formation, migration and transformation mechanisms of halogenated hydrocarbons in this area.