In this study, the biogas was produced by the gradual replacement of cow dung using sewage water and poultry dropping. Cow dung replacement with sewage water showed high utility of the total solids than the control bioreactor. In control bioreactor the total solid reduction is ranged between 10% and 9.8%, whereas in the experimental bioreactor which contained the gradual replacement of cow dung with sewage water, the total solid degradation occurred from 10% to 6.1%. The analysis of biogas production by gradual replacement of cow dung with poultry droppings and sewage water revealed the total solids degradation range from 7.2% to 6.7%. Total solid level reduction is considered to be one of the important parameter for biogas production. Regarding the production of biogas, the gradual replacement of cow dung with sewage water experimental reactor gave more biogas (1421lit/kg of dry matter/day) when compare to the control bioreactor (1007lit/k g of dry matter/day). The maximum gas production also occurred at 80% replacement with sewage water. The gradual replacement of cow dung with poultry droppings supplemented with sewage water revealed the high gas production (1952lit/kg of dry matter/day) than the cow dung replacement with sewage water and control bioreactors. During the gradual replacement of cow dung with poultry droppings and sewage water concluded that there is an excellent biogas production in the 100%replacement of cow dung which in turn indicated that poultry droppings contains more total solid level which can be easily degraded by methanogenic organisms than in cow dung and sewage water can be a good nutrient source for biogas production.