This study investigated how natural organic matter (NOM) affected the aggregation, dissolution and sedimentation of cadmium telluride quantum dots (CdTe QDs) in artificial freshwater and seawater, with a focus on the impact of NOM species and the mechanism of CdTe QDs-NOM interactions. Results found that NOM dispersed CdTe QDs aggregates by providing electrosteric stabilization and promoted the dissolution by facilitating their contact in most cases. Among the tested NOM, fulvic acid (FA) was the most effective for releasing Cd