Up to now, there has been less results from on-site pilot-scale anaerobic co-digestion system, especially for high-rise building application. The objective of this study was to develop an on-site prototype twostage anaerobic digester for co-digestion of food waste and sewage sludge from high-rise building for biogas production. The optimal mixing ratio of food waste to sewage sludge, obtained from laboratoryscale, was found to be 7:1. Then, the prototype two-stage anaerobic digester was further designed and constructed. The results showed that COD and total volatile solid (TVS) reduction could be achieved up to 89 and 74%, respectively with the applied hydraulic retention time (HRT) of 24 days. The methane content of biogas was 64 percent. Up to now, the biogas from on-site production has been utilized for cooking at Chulalongkorn University as a model case study for high-rise building application.