The present invention relates to: a bispecific antibody including an antigen-binding domain that binds to TRAILR2 and an antigen-binding domain that binds to PSMA, or a fragment of said antibody a nucleic acid including a base sequence that encodes said antibody or said antibody fragment a recombinant vector including said nucleic acid a transformant strain including said recombinant vector a method for producing said bispecific antibody or said antibody fragment by using said transformant strain and a detection/measurement reagent, a diagnostic drug, and a therapeutic drug including said bispecific antibody or said antibody fragment.