Abstract: A BLyS antibody, preparation method therefor and application thereof, the BLyS antibody comprising one or more of CDR1, CDR2 and CDR3 of a heavy chain variable region of the BLyS antibody, and/or one or more of CDR1, CDR2 and CDR3 of a light chain variable region of the BLyS antibody. An amino acid sequence of the antibody is shown in a sequence listing. The BLyS antibody has a high affinity, and may observably and effectively seal a BLyS protein at a protein level and a cell level, and prevent the BLyS protein from binding to a receptor. The BLyS antibody lacks a cross-reaction with homologous protein antigens such as human APRIL, and enjoys good biological activity. The BLyS antibody may inhibit the proliferation of human BLyS-induced mouse B cells and may therefore be used for preparing a drug for preventing or treating diseases associated with BLyS expression or dysfunction.