This study was performed to investigate antigenic expression patterns in the course of HSV-1 infection. In SDS-PAGE analysis, HSV-1 antigens were detected, and among them, antigens in the size of 39, 47, 63, 86, 101, 105, 135, 159, and 181 kDa appear to be expressed in the most dominant forms. BALB/c mice were infected with HSV-1 for 29 days and antigenic expression from HSV-1 was investigated by Western blot analysis using anti-HSV-1 sera collected every two days from BALB/c mice infected with HSV-1. Most of HSV-1 antigens appeared sporadically as the infection progressed. However, antigens in the sizes of 63kDa and 135kDa were expressed from day 1 and 3, respectively, and existed continuously during the course of infection for 29 days, suggesting that they are the most dominant antigens inducing immune response durign HSV-1 infection, and they could be the target antigens for the development of vaccines. The isotype levels of IgA, IgGl, and IgM increased till the 17 th day infection and then started to decrease. During this course. IgGl was the most dominant isotype. In an indirect immunofluorescent assay, antibodies exhibited surface binding to the Vero cell infected with HSV-1, demonstrating that HSV-1 antigens are expressed on the surface of Vero cells.