A modified Herpes Simplex Virus (HSV), which has a portion of gD (glycoprotein D) of the glycoproteic envelope deleted and a heterologous single chain antibody inserted in place of such deleted portion; the modified HSV is capable of infecting cells through receptor HER2/ErbB2 but not through receptors HVEM/HveA and nectin1/HveC; uses of the modified HSV and a process of the preparation thereof are also disclosed.