Energy demand rises significantly correlated to human activities in recent years. In contrary, energy supply from unrenewable resource decreases gradually from year to year. OMW as one of the renewable resources has not been expanded well in Indonesia. Therefore, SMFC will answer the alternative technology to generate electricity from OMW. The objectives of this study are conducted to compare of waste volumes on power generation and COD removal in SMFC and determine the optimum waste volume for SMFC application affected by river sediment microorganism source and mixed waste type. SMFC reactor as MFC single chamber was designed by 2.5-liter volume of plastic houseware utilized with single graphene anode and cathode to increase the power generation.The waste volume as the independent variable was adjusted 1/3; 1/2; 2/3 of the 2.5- liter volume of SMFC reactor, whereas river sediment microorganism source and mixed waste were dependent variables. The power density and COD removal percentage in 1/3VR, 1/2VR, and 2/3VR were compared on days 21 which was the typical day of the optimum performance of SMFC. The result shows that power density and COD removal of waste volume 2/3VR was higher than 1/3VR and 1/2VR. Power density of waste volume 2/3VR increased 1.5 - 3 times of power density of waste volume 1/3VR and 1/2VR, respectively. COD removal of waste volume 1/3, 1/2, and 2/3 remained stable. The optimum waste volume, the higher power density and COD removal, in addition to the result that 2/3 of the waste volume was the optimum result.