Abstract: Dissolved organic matter (DOM) is one of the main pollutants in the groundwater of municipal solid waste landfills (MSWLs). However, the DOM characteristics in the groundwater of MSWLs in the red bed zone are still unclear. Therefore, the source, the composition and the spatiotemporal distribution of DOM in the groundwater of MSWLs were studied with fluorescence excitation-emission matrix spectra, based on the field investigation in a typical red bed zone of China. Results indicate that the concentration of TN, TP, Fe, Cd, Hg and Cr (Pi_(standard)=0.001~0.587), except COD_Mn ( Pi_(standard)=1.323~5.392 ), in the groundwater of the landfill groundwater diversion well (DP17), the monitoring well of the landfill groundwater contamination diffusion (KS2~KS6) and the monitoring well of the aquatic groundwater contamination (SC8) could meet the class Ⅲ limits of groundwater quality. Besides, the Mn in the SC8 well (Pi_(standard)=1.140) exceeded the limit. Compared to the background well (BJ1), the Pi _(background) of pollutants in the groundwater ranged from 0.703 to 142.991. It is indicated that the groundwater in the investigated zone had been affected by different pollution sources. The concentration of TP in the SC8 (Pi_(background)=34.719) was greatly higher than that in BJ1 and other monitoring wells. The TP in the monitoring wells of mixed pollution sources (HH) including both the agricultural and the living pollution source (Pi_(background)=7.812) was also obviously higher than that in the monitoring well of agricultural pollution source (NY7， Pi_(background)=1). Therefore, the TP can be used as a groundwater characteristic pollutant derived from the aquatic source and the living source. The groundwater had been affected by different nitrogen sources in the investigated zone due to the Pi _(background) of TN in the NY7 well, the KS2~KS6 wells and the HH9~HH16 wells was between 2.103 and 5.169. The DOM in the landfill leachate and in the nearby groundwater included the humic-like substances， the fulvic-like substances and the tryptophan-like protein substances. The groundwater contamination of DOM derived from the landfill was just limited to its vicinity. It is inferred that the groundwater diversion well could effectively reduce the impact of leachate leakage on the groundwater. There was a significant difference of DOM humification degree in groundwater between in wet season (HIX _average = 3.99) and dry season (HIX _average = 10.69). The fluorescence intensity of the humic acid and the fulvic acid in the DP17 well were 3.1~11.9 and 1.9~8.3 times higher than the monitoring wells of other pollution sources, respectively. Therefore, they can be used as indicative pollutants for the groundwater contamination of DOM derived from the MSWLs.