摘要：AD (anaerobic digestion) is a beneficial and efficient technique for the treatment of agricultural wastes, food wastes and wastes water to produce renewable energy. Solid agricultural are potential renewable energy resoures. Biogas production by co-digestion of mixed Napier Pak Chong I and food waste at thermophilic temperature using anaerobic digestion in cow dung and chicken dung as the seed inoculums were investigated. The total reactor volume of the co-digester reactor was 7.94 m 3, which was equipped with pump, and it was operated continuously for the 20 days as a pilot scale at 50 ?C. The Napier Pak Chong I was cut into 2 mm sections, and the initial VS (volatile solids) was 30%. The initial VS of food waste were 70%. Two pilot-scale digesters filled with Napier Pak Chong I and food waste, which both digesters contained 476 kg of Napier Pak Chong I mixed 305 L of food waste, and 1,305 L of water. There were carried out to investigate the optimum C/N (carbon to nitrogen) ratio for effective biogas production. The slurry raw materials provided sufficient buffering capacity to maintain appropriate pH values (between 7.0 and 8.0). Digester I was designed for 1.98 m 3 of cow dung as the seed inoculum while digester II was designed to establish 1.98 m 3 of chicken dung as the seed inoculum. Gas detector performs analysis gas production. The experimental results indicate that total biogas production was 2.19 m 3 /day in digester I and 1.86 m 3 /day from digester II, resulting in specific methane yields of 1.26 m 3 CH 4 /kgVS and 1.07 m 3 CH 4 /kgVS added, respectively. Biogas production in digester I was directly correlated with temperature.