A humanized anti-IgE antibody is disclosed. The antibody is capable of binding to free IgE, membrane-bound IgE on B lymphocytes, and IgE bound by CD23, but not to IgE bound by FcɛRI. The CDR-H1, CDR-H2 and CDR-H3 of the antibody respectively comprise the amino acid sequences of SEQ ID NOs: 5-7, and the CDR-L1, CDR-L2 and CDR-L3 of the antibody respectively comprise the amino acid sequences of SEQ ID NOs: 8-10.
