The dissolved organic matter (DOM) was isolated and purified from landfill and incineration leachate, and all the isolated fractions were characterized using acid-base titration, UV-VIS (ultraviolet-visible), FTIR spectroscopic methods and element measurement. As shown by acid-base titration, the total acidity and carboxylic groups followed HyI > FA > HA and FA> HA> HyI respectively, and all the samples from incineration leachate had more acidity and carboxylic groups than those from landfill leachate. UV-VIS analysis showed that the humification of humics in leachate followed C-HA > L-HA > I-HA and L-FA > I-FA. FTIR spectroscopic indicated that the humics from the same leachate had similar molecular structure, and L-HA had more aromatic groups than L-FA, while L-FA had more acid groups. Element measurement indicated that the content of N in leachate humic substance was higher than that from other surroundings, and the aromatic content in humic substance from landfill leachate was higher than that from incineration leachate, which was also obtained by UV-VIS analysis.