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We evaluated the settling ability and dewaterability of granulated methane-oxidizing bacteria (GMOB) after granulation using a continuous-flow reactor. A comparative analysis on the settling and dewatering characteristics due to changes in the sludge retention time (SRT) during cultivation of the GMOB was also conducted for SRTs of 10, 15 and 20 days. In assessing dewaterability, the specific resistance to filtration (SRF) of the activated sludge and GMOB was found to be 8.21×10 13 --2.38×10 14 and 4.88×10 12 --1.98×10 13 m/kg, respectively. It was also confirmed that as the SRT decreased, the SRF of the GMOB increased. In the case of the bound EPS, the activated sludge registered 147.5 mg/g-VSS while the GMOB exhibited 171--177.2 mg/g-VSS. In the case of the soluble EPS in effluent, the activated sludge measured 62 mg/L and the GMOB had 17.4--21.4 mg/L. The particle size analysis showed that the mean particle diameters of the GMOB were 402, 369, and 350 µm, respectively, at the SRTs of 20, 15 and 10 days. In addition, it was found that the GMOB had a larger mean particle diameter and exhibited much better settleability and dewaterability than the activated sludge did.