Medium Cut-Off Membrane has been an important evolution in the field of hemodialysis for the past years. Its advantages are mainly reflected in the significant improvement of the clearance of large medium molecular uremia toxins at the moment, more and more relevant clinical trials are being revolved to verify the clinical feasibility and long-term benefits. The nomenclature and theoretical advantages of medium cut-off membrane, and related technologies of Expanded Hemodialysis as well as its clinical applications were briefly described below.