Provided is porous hollow fiber membrane for processing protein-containing liquids, said membrane enabling a material for removal such as a small-diameter virus contained in a solution to be efficiently separated and removed, while simultaneously enabling a useful material for recovery such as a high concentration protein to be efficiently pass through. The porous hollow fiber membrane comprises an asymmetrical structure having a dense layer on the outside layer alone, and contains a hydrophobic polymer and a first hydrophilic polymer. The surface and porous portion of the hollow membrane is covered by a second hydrophilic polymer, and the hydrophobic polymer is a polysulfone polymer. The first hydrophilic polymer is a vinylpyrrolidone/vinyl acetate copolymer, and the second hydrophilic polymer is a polysaccharide or a polysaccharide derivative. This porous hollow membrane is obtained through a step in which a porous hollow membrane is formed using a stock solution obtained by co-dissolving the hydrophobic polymer and the first hydrophilic polymer in the same solvent, and then covering the surface and porous portion of the hollow membrane with the second hydrophilic polymer.L'invention fournit une membrane poreuse à fibres creuses destinée au traitement d'un liquide comprenant des protéines qui permet à la fois la séparation ainsi que le retrait de manière efficace de substances à retirer telles que des virus de petit diamètre, ou similaire, contenus dans une solution, et une perméation efficace de substances de récupération utiles telles que des protéines hautement concentrées, ou similaire. Cette membrane poreuse à fibres creuses est constituée d'une structure asymétrique possédant une couche dense uniquement sur une couche externe, et contient un polymère hydrophobe et un premier polymère hydrophile. La surface de ladite membrane à fibres creuses et une partie poreuse sont recouvertes d'un second polymère hydrophile. Ledit polymère hydrophobe consiste en un polym
