Abstract: The present disclosure provides an MABR-based method for treating rare earth mine tailwater, comprising: introducing rare earth mine tailwater into a sedimentation pond and simultaneously injecting pig farm breeding tailwater into the sedimentation pond, and fully mixing the two in the sedimentation pond for solid particulate sedimentation; performing pH adjustment, MABR enhancement treatment, percolation treatment with a percolation dam, and ecological purification with an ecological purification pond; and overflowing and discharging the rare earth mine tailwater purified by the ecological purification pond to a natural water body.