Biogas as a source of renewable energy can be produced from variety of organic materials such as agricultural residue, animal manure, municipal wastewater, etc. Anaerobic digestion of organic material is decomposing of organic content in the absence of oxygen. In this procedure organic material is decomposed by bacteria to variety of end product in which the main gasses are Methane and Carbon dioxide. The application of anaerobic digestion for biogas generation in Iran is referred to Sheikh Baha al-Din Muhammad Ameli's bathroom in 16 century, which used generated biogas from bath wastewater for boiling water. In this study the basic design and fundamental information of Baha al-Din's bathroom is used for generation of biogas. In modified procedure 24.8 m3/day biogas generate per 2000 Kg of cow manure. This simple design could be used as a source of energy in rural area of developing country.