The present invention relates to a method for screening an anti-NRP1 antibody or an antigen-binding fragment thereof using NRP1-overexpressing patient-derived cells and an animal model comprising the same and, more particularly, to a method for screening an antibody or an antigen-binding fragment thereof through in vitro and in vivo panning using a patient-derived cell containing NRP1 and an animal model transplanted with the same, respectively.