Batch digestion of municipal garbage was carried out under room temperature conditions (26 +/- 4 degrees C) for 240 days. The ultimate biogas production potential of municipal garbage was found to be 0.661 m(3)/kg volatile solids. The experimental and ultimate gas yields obtained from municipal garbage compared well with the yields obtained from other types of solid wastes. A mathematical model was developed to predict both ultimate biodegradable substrate concentration as well as ultimate biogas production. The ultimate bioenergy yield, ultimate anaerobic biodegradability of the substrate and the overall bioprocess conversion efficiency were evaluated from observations to be 18,145 kJ/kg volatile solids, 89.79 and 95.44%, respectively. The total biogas yield from municipal garbage per kg dry matter was observed to be 0.5 m(3) and the average methane content of the biogas was observed to be 70 %vol.