<p>DNAPLs are volatile, hardly degradable, highly toxic, and low solubility, which seriously threatens the ecological environment system and human health. While the fine characterization of DNAPLs migration process in porous media is crucial for remediating the contaminated sites. In order to finely characterize the migration process of DNAPLs in porous media, trichloroethylene (TCE) was selected as a typical DNAPLs pollutant in this paper. Then, based on the laboratory sand box model, image method and electrical resistivity tomography (ERT) technology were used to monitor the migration process of DNAPLs in saturated heterogeneous and homogeneous porous media, and the migration rules of TCE in different porous media were discussed and verified to achieve fine characterization of pollutant. The results of the sand box experiment indicated that when the particle size of heterogeneous quartz sand was small, TCE mainly migrated horizontally, and with the increase of quartz sand particle size, the vertical migration gradually dominated. For the homogeneous quartz sand media, TCE was also mainly horizontally migrated, supplemented by vertical migration. With the increase of pollutant injection time, TCE was mainly vertically migrated. When approaching the bottom of the sand box, the vertical migration speed of TCE in both heterogeneous and homogeneous quartz sand media slowed down, and the DNAPLs contamination pool could be formed at the bottom of the sand box. Generally, this paper uses the image method to visually reflect the migration of DNAPLs, and indirectly characterizes the distribution characteristics of DNAPLs by ERT technology, which is of great significance for studying the migration rule of DNAPLs and determining the pollution scope and degree, and can provide certain guiding value for fine characterization and low-cost remediation of DNAPLs pollutants in actual contaminated sites.</p>