Abstract: Aiming to overcome the shortcomings existing in the traditional sanitary landfill，simulation researches of semiaerobic bioreactor landfill by laboratory experiments were conducted． Two systems，distinguished by the airway diameters，had been set up and operated continuously． The results demonstrated that both the waste and the leachate in the bioreactor changed considerably in the duration． The settlement ratio achieved nearly 40%，the organic matters in solid waste reduced to 24%， and the COD，BOD5 ，TOC，ammonia nitrogen and TN concentrations of the leachate were reduced significantly，decreased to 3 643 mg /L，73 mg /L，1 284 mg /L，67 mg /L，109 mg /L，respectively． The VFA could drop to 20 mmol /L and the B/C ratio to a level of 0. 02 ～ 0. 03，which collectively means that the leachate and also the remaining waste were rarely biologically degradable． All the characteristics revealed that a favorable degradation was achieved，the waste got reduced，the pollutants abated，and the overall landfill primarily stabilized