Effects of fire on carbon balance in tropical peatland have been concerned as a serious issue in the world. To evaluate the effect on the leaching of dissolved organic carbon (DOC) from peatland, DOC concentrations of groundwater were determined at three different tropical peatland ecosystems in Central Kalimantan, Indonesia. Water samples were collected at unburnt site (SF) in Sabangau swamp forest, and at unburnt (KF) and burnt sites (KB) in Kalampangan drained swamp forest from July to November in 2010. Physicochemical parameters of the groundwater, such as electrical conductivity (EC), pH, groundwater level and temperature were also measured at the sites. Temporal variations in DOC concentration were synchronized with water level, EC and pH values. DOC has been increased with increasing EC and decreasing pH. The highest DOC was measured at KF (13.42 to 73.40 mg L^-1), whereas the lowest DOC was at SF (6.41 to 49.36 mg L^-1). DOC was lower at KB (10.83 to 29.81 mg L^-1) than KF site. It was indicated that fire significantly decreased the DOC concentration of groundwater. On the other hand, the lowest EC and the highest temperature were measured at KB, although pH value was not so different among the sites.