Herpes simplex virus (HSV) infection is the most common sexually transmitted viral disease. According epidemiological studies almost one quarter of the adult population in Bulgaria is seropositive for HSV-2. High prevalence of infection, asymptomatic course and limited diagnostic resources increased risk of neonatal acquisition of HSV from pregnant women. The etiology, epidemiology, clinical presentation, diagnostic methods and factors influencing neonatal transmission of HSV are presented.