A method of screening an antibody comprises preparing a serum having a target antibody and a non-target antibody; providing the serum with a first antigen that specifically binds the target antibody to obtain a first mixture; selectively obtaining the first conjugate by separating the first conjugate from the non-target antibody in the first mixture; dissociating the first conjugate, and a redundant non-target antibody adsorbed to the first conjugate into the first antigen, the target antibody and the redundant non-target antibody; removing the first antigen to obtain a second mixture of the target antibody and the redundant non-target antibody; providing the second mixture with a second antigen to form a second conjugate, so that third mixture including the target antibody and the second conjugate may be obtained; and selectively obtaining a target antibody by separating the second conjugate from the target antibody in the third mixture.