It is a separation membrane driven by concentration difference. According to the particle size of the separated solute, the dialysis membrane is required to have corresponding micropores with uniform pore size. Organic polymer homogeneous membrane with pore size below 65438 0 μ m is an uncharged porous membrane, which is mainly used for cellulose dialysis membrane of artificial kidney at present. Commonly used preparation materials include cuprammonia regenerated cellulose, cellulose acetate, polyacrylonitrile, ethylene-vinyl alcohol polymer, polymethylmethacrylate, polysulfone, polyacrylamide and so on.