" The purpose of this research paper is to investigate bio gas production process. The aims to determine the process condition that maximize biogas generation and the appropriate manure water mixture that enhance biogas output. This paper also present a design of biogas digester for backyard or farm use. Biogas is the product of the digestive action of anaerobic during fermentation of organic materials. The environment of the processing microbial bacteria contributes largely to the stimulation of biogas production. The more conducive the process condition to the bacteria growth , the higher is the bio gas production a. oxygen free anaerobic digestion b. steady temperature inside the digester tank at mesophilic temperature of about 36 deg.C c. pH or degree of acidity of more than 6.5 but less 7.5 d) alkalinity of about 3000 milligrams per liter of slury e.) sufficient amount of nutrient, phosphorous and nitrogen f.) absence of inhibiting salts,heavy metals and excess ammonia g.)constant solids loading rate at 2 to 3 kg/ cubic m. of digester volume per day. Aside from the process condition, bio gas output is also enhanced through the use of appropriate slurry mixture. The water manure proportion provides the appropriate acidity as well as the desired ratio of carbon and nitrogen needed by the bacteria to survive. Proper digestion proceeds at an optimum rate when the carbon content of the slurry or materials used are about 25 times the nitrogen content. Using hog manure, the slurry mixture of 1:1:0.20( water -manure-starter) and 1:1:0.25 yields the highest volume of bio gas. Every kilogram of water requires kilograms of hog manure and 1/4 kilogram of slurry starter to attain the highest production rate of biogas. As to the working model of biogas digester presented in this paper, it generates 11,427.73 Btu of fuel energy per day out of digested wastes from 20 pig heads. The total volume of the tank is 5.96 cubic meters and has construction cost of 21,036.05. This paper recommends the formulation of bio gas technological and process designs suitable for domestic use. Extensive research and development activities through pilot plant stage must be undertaken with full support and funding from the government. Furthermore, national policy should also support extensive research and studies on the wider application of bio gas fuel as source of energy. Information on this basic in commercializing. "