HIV-1 is an envelope virus. Two glycoprotein subunits, gp120 and gp41, are on the virus membrane and mediate the virus entry. The membrane fusion events leading to HIV entry into the target cell are initiated by the binding of gp120 to CD4 and subsequently to a co-receptor, CXCR4 or CCR5. Then the conformation of gp41 has also changed, resulting in the fusion between the viral and cellular membranes. Many antibodies, proteins, saccharides, peptides and small molecule compounds which bind to gp120 can deter the progress of virus entry. This review discusses recent progress in the development of anti-HIV agents targeting gp120.