Environmental pollution, lack of energy, increase in greenhouse gases and global warming are the greatest human challenges in the 21st century that threatens his life. Due to the impressive growth of the Industries in the world, and in order to reduce environmental pollutions, energy costs, dependence on fossil fuels and global warming, attentions has been focused on renewable energies. One of the ways to produce renewable energy is -Biogas production- control of produced methane from anaerobic digestion of excreta and wastes. In this process, oxygen is not consumed, it doesn't need much nutrients and the produced methane is usable as a energy source. Also by production of biogas, natural gas and oil resources are extracted at a lower rate and these resources are reserved for the future. It is worth mentioning that the produced biogas can be used for cooking, heating, power generation and automotive fuel. In this project, bio-methane potential of several plant and animal residues have been investigated and determined. The plant wastes include: coffee pulp waste, residue of sesame oil extract, residue of cichorium plant distillation, residue of cumin plant distillation, residue of citrus bigardia plant distillation, and date kernel. The animal wastes include: cow manure, laying hens manure, broiler chicken manure, and egg powder. Also three pretreatments were applied, i.e. physical, oven heating, and autoclave heating at 120°C. In this study, two tests have been performed to produce biogas at mesophilic conditions at 37 ± 0.5? which continued for 54 and 60 days. In each test, there were 18 duplicate reactors with different content, that is, in each test there were 36 reactors. Each reactor contained inoculum (cow rumen fluid), water and substrate. A variety of plant and animal residues either individual or combined were used as substrate. In order to measure the volume of the produced biogas, the water column displacement method was used. Finally, gas composition and methane percentage were obtained by means of a pressure lock syringe and injection into a gas chromatography system. In the first test, which continued for 54 days, cow manure with production of 485.58 had the maximum methane production and the oven pre-treated residue of citrus bigardia plant distillation with production of 154.30 had the lowest methane production. In the second test which continued for 60 days, oven pre-treated coffee pulp waste with production of 502.03 had the maximum methane production and the oven pre-treated date kernel with production of 150.66 had the minimum methane production. The results were analyzed by specifying the composition of the collected biogas and performing elemental analysis and determining the ratio of carbon to nitrogen. Keywords Renewable Energy, Anaerobic digestion, Methane, Biogas, Plant and Animal Residues, Gas Chromatography, Elemental analysis