The present invention aims to provide a fiber for protein adsorption and a column for protein adsorption which show less elution and hence are safe, and have high protein adsorption capacity. The present invention provides a fiber for protein adsorption, wherein the fiber has a water absorption percentage of 1 to 50%, and the fiber comprises a polymer containing as repeat units an aromatic hydrocarbon or a derivative thereof, wherein part of aromatic rings contained in the repeat units are cross-linked through a structure represented by the following General Formula (I). The present invention also provides a column for protein adsorption using it. Here, A in the General Formula is selected from an alkyl aliphatic group, phenyl aromatic group, and amino group.
