A carrier for blood component adsorption includes a water-insoluble carrier composed of a fiber or particle, the water-insoluble carrier having a surface to which a functional group(s) is/are introduced, the functional group(s) containing an acidic functional group selected from the group consisting of the sulfate group, sulfite group and sulfonate group； and containing an amino group； the fiber having a fiber diameter of, or the particle having a particle diameter of, 0.5 to 20 μm.
