Manure is the main source of “Biomass” from which biogas may be produced and is known as one of the forms of renewable energy. This is the result of an anaerobic bacteria activity and biogas is produced through anaerobic digesters which are called inside reactors and contain methane (70-55%), carbon dioxide (45-30%), and minimal traces of nitrogen, hydrogen, hydrogen sulfide and moisture. In this study, four non-contiguous batch reactors with a volume of 2.2 liters, height of 350 mm, diameter of 90 mm and thickness of 5 mm were assembled and the influence of different substrates on the production of biogas and factors such as pH, percent total solids (TS), percent volatile solids (VS) and ammonia were investigated. Gas chromatography(GC) was used for gas analysis and peaks for analyzing gas compounds were determined in ABC software. Experiments were conducted over the course of 55 days and substrates were loaded in the reactors. The substrates contained manure with 7% total solids, 7% total solids with fried kitchen oil, manure with 7% total solids with molasses and manure with 3% total solids. The trend in substrates reactions inside reactors indicated that in the first reactor a 57% reduction in TS and 53.5% in VS, in the second reactor a 16.5% reduction in TS and 12.28% in VS, in the third reactor a 21.29% reduction in TS and 28.06% in VS and in the fourth reactor a 31.3% reduction in TS and 18.7% in VS were observed, respectively. Due to lower pH level in the reactor containing manure with 7% TS with molasses, methane production rate experienced a sharp decline, but methane produced in other three remaining reactors, was measured to be about 70% of the biogas produced. The effect of fried kitchen oil as co-digestion material on methane yield was evaluated and was shown to produce methane 3 times as much as were it was absent in the first reactor. The ammonia was measured for all 4 reactors and was observed to be in the allowable range. The methane produced in the first, second, third and fourth reactor were 9.57, 39.18, 0.5 and 25.7 liters per kilogram of fresh manure, respectively. Keywords: non-contiguous batch reactor, anaerobic digestion, biogas, cow manure, methane.