[Problem] To provide an anti-EphA4 antibody or an EphA4-binding fragment thereof that is capable of binding to EphA4 and inhibiting the binding of EphA4 and the ligands thereof, and a pharmaceutical composition containing these as an active ingredient. [Solution] A mouse anti-EphA4 antibody having binding affinity for EphA4 was acquired, and the sequence of the complementarity-determining region (CDR) of the mouse anti-EphA4 antibody was identified. This made it possible to produce a humanized antibody including the CDR sequence of the mouse anti-EphA4 antibody in the variable regions of the heavy and light chains.
