The purpose of this study is to develop the advanced and high efficient upflow anaerobic reactor and put in practical use. To achieve this purpose, we built 4 reactors. 25㎥ scale each, and brought the seeding sludge for filling the reactors from K sewage treatment plant. The reactors were designed based on labotary scale reactors performed before and operated with changing the settling compartment and GSS device. During the operation, we came to get the result of DW-process characteristics. The seperation rate of gas and solid was elevated by increasing contact area and R2, R3 and R4 reactor showed good protection efficiency of 30.2, 52.5 and 23.0% from wash-out of sludge. All of 4 reactors gave over 90% COD_(nm) efficiency, 8hr HRT 6-10㎏ COD/㎥/day OLR and over 80% methane content in gas produced in the reactors.