The present invention relates to an anti-BTLA antibody or an antigen-binding fragment thereof, the anti-BTLA antibody or antigen-binding fragment thereof comprises at least one light chain CDR structure domain selected from among SEQ ID NO : 7, 8, 9, 10, 11, 12, 16, 17, 18, 22, 23, 24, 31, 32 and 33 and/or at least one heavy chain CDR structure domain selected from among SEQ ID NO : 1, 2, 3, 4, 5, 6, 13, 14, 15, 19, 20, 21, 25, 26, 27, 28, 29 and 30. The present invention also relates to nucleic acid molecules that encode the antibody or antigen-binding fragment thereof, a corresponding expression vector and a host cell, as well as a therapeutic use of the antibody or an antigen-binding fragment, nucleic acid molecules, an expression vector and a host cell thereof.