Herpes simplex virus type 1 (HSV-1) is an important human pathogenic virus. It is urgent to develop novel antiviral targets because of the limited treatment options and the emergence of drug resistant strains. In this study, we tested the antiviral activity of lupeol, a triterpenoid compound, against HSV-1 and acyclovir (ACV) resistant strains. Lupeol significantly inhibited HSV-1 (F strain) and ACV-resistant strains including HSV-1/106, HSV-1/153, and HSV-1/Blue. Lupeol activity of the HSV-1α0 and α4 promoters, therefore down regulating the expression of the α0, α4, and α27 genes. Collectively, lupeol showed strong antiviral activity against HSV-1 and ACV-resistant strains, and could be a promising therapeutic candidate for HSV-1 pathogenesis. Keywords: herpes simplex virus 1; lupeol; ACV-resistant strains; promoter.