Extracts from herpes simplex virus type 2 (HSV-2)-infected cells were subjected to affinity chromatography with gel-bound Helix pomatia lectin (HPA). Only one HSV-2-specified glycoprotein was isolated by this procedure and the glycoprotein had an apparent molecular weight of 130 000 (130K). The HPA-binding glycoprotein was genetically mapped, using HSV-1 X HSV-2 intertypic recombinants into the short component of the HSV-2 genome. The mapping position, electrophoretic mobility and the antigenic properties of the HPA-binding protein indicated that it was unrelated to glycoprotein C (gC), which is the HPA-binding glycoprotein in HSV-1-infected cells, and distinct from gE and gD which map in the S component. The glycoprotein was almost quantitatively precipitated by monoclonal antibody AP1, specific for glycoprotein g92K and it also reacted with monoclonal antibody 1206-3, specific for the HSV-2 glycoprotein G previously described. It is concluded that the isolated glycoprotein is identical to g92K and consequently also to the HSV-2-specific glycoprotein G.