The invention relates to a method for conveying biogas at a long distance and low cost. The method is characterized in that a large biogas digester with the biogas output pressure p is networked withthe periphery of the large biogas digester as much as possible, especially a biogas digester and a septic tank which are scrapped at the user end of the biogas pipeline at a long distance, and a gas cabinet with the biogas height of no more than h = P/rho g -0.3m is built at the position h = p/rho g m near the liquid surface of the pond near the user end of the biogas pipeline for long-distance transportation. The device for conveying biogas at a long distance and low cost comprises a biogas digester, a septic tank, a water pond and a gas collecting hood, wherein the biogas digester, the septic tank and the gas collecting hood are connected with the large biogas digester through a connecting pipeline, and the connecting pipeline is provided with a branch pipe for conveying to the user. According to the method and device, only the existing waste biogas digester or the septic tank needs to be used, so that the biogas can be conveyed at a long distance and low cost, the method and deviceis safe and environment-friendly, and has economic benefits.