The present invention provides a bead for blood treatment, which is a bead for blood treatment having a porous bead and a polymer supported on the surface of the porous bead； the porous bead is selected from At least one resin in the group consisting of acrylic resin, styrene resin, and cellulose resin； the above polymer contains a specific monomer as defined in the specification of the present invention as a monomer unit.本發明提供一種血液處理用珠粒，其係具有多孔質珠粒、及被擔持於上述多孔質珠粒表面上之聚合物的血液處理用珠粒；上述多孔質珠粒係由選自於丙烯酸系樹脂、苯乙烯系樹脂、及纖維素系樹脂所組成之群組中的至少一種樹脂所構成；上述聚合物包含本發明說明書所定義之特定單體作為單體單元。
