A monoclonal antibody useful for clinical application which recognizes the conserved region of V3-PND region of glycoprotein antigen having a molecular weight of about 1.2.times.10.sup.5 daltons (gp120) on a coating membrane of human immunodeficiency virus (HIV) and which has an ability to neutralize a broad range of various HIV variants, or a fragment thereof, and the chimeric and humanized antibodies derived therefrom are provided. By using as an immunogen a plurality of peptides having PND-Tip region containing the highly conserved GPGR sequence within PND of HIV gp120, a monoclonal antibody having a neutralizing activity to many HIV variants can be prepared. By transplanting the gene fragment coding for the variable region of said monoclonal antibody or complementarity determining region (CDR) of said region to a human antibody gene, a chimeric antibody or a reshaped antibody having an anti-HIV neutralizing activity which are effective for clinical application can be obtained.