In this study we further investigated the inhibiting activity of bLf against herpes simplex virus type 1 (HSV-1) in Green Monkey Kidney (GMK) cells and found that, in addition to the viral adsorption step, bLf also targets the HSV-1 entry process and cell-to-cell viral spread. Our study showed that the inhibition of HSV-1 infectivity by bLf is dependent on its interaction with specific structural viral proteins. Apart from the prevention of early phases of viral infection, cell-to-cell spread inhibition activity of HSV-1 by bLf confirmed that this protein is an outstanding candidate for the treatment of herpetic infections since it would offer the advantage to prevent also viral infections caused by cell-associated virus.