Abstract: By using self-innovating technology and establishing USR facility system,some problems of harmless treatment and comprehensive resource utilization for sewage from large pig farm were solved. Three biogas＇ produced in pig farm is applied for keeping warm for pig farm and fishpond, energy resources for farm and as an organic fertilizer, so a chain can form as pig- producing-stool-biogas-comprehensive application of biogas-pollution-free agricultural production ,which not only can improve health environment and increase productivity, but also can provide high quality organic fertilizer for developing eco-agriculture and organic agricultural product. Resource utilization and industry cycle economic construction mode of contaminant from large pig farm were established. The construction content, technological process and technology application of large biogas digester matching construction project for pig farm were introduced.