The up flow anaerobic sludge blanket (UASB) reactor is an important anaerobic treatment method for treating organic waste in various forms. Biogas production in Syria is still in its primitive stage and has become an urgent necessity, coupled with the presence of a significant amount of primary biomass, estimated at 379 million tons annually, which can generate approximately 4.6 billion cubic meters of biogas when processed. A laboratory-scale UASB reactor with a diameter of 19 cm and a height of 115 cm was designed to maximize methane gas production. The mixing ratios of cow dung with food waste used were 20%, 30%, and 40% at a temperature of 35 degrees Celsius for a duration of 35 days. Several parameters that affect gas production were measured. The methane gas production was 7.4 L at 20% food waste, 7.1 L at 40% food waste, and 6.6 L at 60% food waste. The highest biogas yield was achieved with 20% of food waste and cow dung due to its proximity to the ideal carbon to nitrogen (C/N) ratio.