This invention relates to a refuse landfill leachate wastewater treatment system comprising a collection well, an adjustment tank, a filter, a comprehensive treatment system having a multi-stage anoxic/aerobic pool and a membrane biological reactor. The process of treatment is: waste water enters a adjustment tanke in which water quality and quantity are adjusted; subsequently, enters a filter, the water discharged from the filter and enters a comprehensive treatment system having a multi-stage anoxic/aerobic pool and a membrane biological reactor, wherein waster water is bio-chemically treated to remove the organic substances, nitrogen and ammonia, and then the wastewater is discharged into a catalyzed oxidation tower; the organic substance in waste water is oxidized on effect of ozone and under the existing catalyst function and then the biochemical capacity thereof is enhanced; and then the catalyzed and oxidized waste water enters carbon filter pool, the remaining contaminated matter can be further removed by degradation of the anoxic oxidation of the biological membrane on the packing material in pool, then the output water meets the requirement of National Standard or other relevant industrial standards.