The fight against herpesvirus infections is an urgent task because the herpes simplex virus (HSV) is very common among the human population and causes a wide range of diseases, ranging from relatively mild primary skin lesions to severe and often fatal episodes of encephalitis. The development of antisense technology with the use of antisense oligonucleotides (AO) is a promising step in this direction. To solve one of the main problems of delivering AO in cells, we prepared Si~NH2•AO nanocomplexes consisting of antisense oligonucleotides immobilized on aminosilanol nanoparticles as vehicles. Several nanocomplexes that contained AOs were tested for their activity against HSV-1, and two of them were shown to be the most efficient in inhibiting the virus replication by 2–2.5 orders of magnitude