To ensure the aquatic environment security and promote the sustainable development of nanotechnology, the interactions between nanomaterials and environmental nanopollutants (humic acid and sodium dodecyl benzene sulfonate) were investigated. The effects of the surrounding solution chemistry (pH and ionic strength) on the interaction were discussed. The results suggested that the interaction between nanomaterials and environmental nanopollutants could inhibit the aggregation of nanoparticles, and then enhance their mobility in aquatic environments. The interaction was affected by pH and ionic strength. The absorbed content of humic acid and SDBS on the surface of TiO₂ nanoparticles increased near the pHpzc (point zero of charge) due to the charge screening effect. It also increased with the increasing ionic strength due to the compression of the electric double layer. The interaction mechanisms between nanomaterials and environmental nanopollutants were discussed. The interaction process could be divided into three processes, including aggregation, approaching and strong interaction. The differences of interaction mechanisms between humic acid and SDBS were also discussed.