Compost leachates were collected to investigate the influence of the composition and removal of volatile fatty acids (VFAs), humic-like substances (HSs), and dissolved organic nitrogen (DON) on heavy metal distribution during the leachate treatment process. The results showed that acetic and propionic acids accounted for 81.3 to 93.84% of VFAs, and that these acids were removed by the anaerobic-aerobic process. Humic- and fulvic-like substances were detected by excitation-emission matrix spectroscopy coupled with parallel factor analysis, and their content significantly decreased after the anaerobic and membrane treatments. DON in compost leachates ranged from 26.53 mg L(-1) to 919.46 mg L(-1), comprised of dissolved free amino acids and the protein-like matter bound to humic- and fulvic-like substances, and was removed by the aerobic process. Correlation analysis showed that Mn, Ni, and Pb were bound to VFAs and protein-, fulvic-, and humic-like substances in the leachates. Co was primarily bound to fulvic- and humic-like matter and inorganic sulfurs, whereas Cu, Zn, and Cd interacted with inorganic sulfur.