Chickenpox is a common childhood infection that generally resolves without complications. But maternal chickenpox near term, or soon after delivery, can cause severe or fatal illness in the newborn. The severity of neonatal chickenpox is closely related to the time of maternal infection and the fatality is reported up to 30%. Although chickenpox is thought to be a mild disease, complications are frequent in neonates and immunocompromised children. The diagnosis of neonatal chickenpox is usually based on the typical clinical feature, the characteristic point in time and the maternal history of chickenpox. Serologic methods have been widely used to confirm clinical diagnosis. To prevent severe neonatal chickenpox, passive immunization is indicated. If varicella occurs, acyclovir treatment has to be done promptly. But the use of acyclovir in symptomatic healthy infant is controversial. We report a case of neonatal chickenpox that was infected by an asymptomatic infected mother and rapid improvement of varicella skin lesions without complications after intravenous acyclovir administration.