The present invention provides a humanized anti-human ±9 integrin antibody having improved activity and/or property as compared to donor mouse anti-human ±9 integrin antibody, namely, a humanized anti-human ±9 integrin antibody comprising a heavy-chain variable region consisting of the amino acid sequence shown by SEQ ID NO: 1 or the amino acid sequence shown by SEQ ID NO: 1 wherein one or several amino acids are substituted, deleted, inserted and/or added and a light-chain variable region consisting of the amino acid sequence shown by SEQ ID NO: 61 or the amino acid sequence shown by SEQ ID NO: 61 wherein one or several amino acids are substituted, deleted, inserted and/or added, as well as a means for preventing or treating various diseases involving human ±9 integrin in their pathogenesis, which uses the antibody.