An adsorbent for the removal of blood cells, which is formed from a hydrophobic polymer resin and has a surface center line average roughness (Ra) of 5 to 100 nm. The hydrophobic polymer resin is preferably a polyarylate resin (PAR), polyethersulfone resin (PES), polysulfone resin (PSF), or a polymer alloy consisting of two or more of these resins. The adsorbent for the removal of blood cells can take the form of beads, hollow fibers, or solid fibers.
