To investigate the interaction of herpes simplex virus type 1 (HSV-1) with the cell surface, we studied the formation of complexes by HSV-1 virion proteins with biotinylated cell membrane components. HSV-1 virion proteins reactive with surface components of HEp-2 and other cells were identified as gC, gB, and gD. Results from competition experiments suggested that binding of gC, gB, and gD occurred in a noncooperative way. The observed complex formation could be specifically blocked by monospecific rabbit antisera against gB and gD. The interaction of gD with the cell surface was also inhibited by monoclonal antibody IV3.4., whereas other gD-specific monoclonal antibodies, despite their high neutralizing activity, were not able to inhibit this interaction. Taken together, these data provide direct evidence that at least three of the seven known HSV-1 glycoproteins are able to form complexes with cellular surface structures.