This study demonstrates the first case report in which an NK Cell deficiency initially presented as an asymptomatic disseminated herpes simplex viremia (HSV). A pre-term 13- day- old patient presented with disseminated HSV after investigation because his twin brother was found to have HSV vesicular lesions. The patient remained asymptomatic throughout the entire hospital course. While 40% of neonates never exhibit vesicular lesions, most of the infants will be symptomatic with DIC and/or respiratory and/or hepatic failure. The HSV development in his twin brother prompted immediate multiple HSV PCR testing even though he was asymptomatic. The results were positive for HSV in both plasma & nasopharynx. He received intravenous acyclovir treatment for 21 days. Both CSF & brain MRI studies demonstrated no CNS involvement. He was discharged home with oral acyclovir for one year. Two months after being off acyclovir he developed herpetic vesicles which resolved with acyclovir treatment. Currently, he is on chronic acyclovir treatment. Lymphocyte enumeration tests demonstrated NK cell deficiency. Typically, HSV is a virulent symptomatic infection especially when it presents with viremia. Here we have a case of asymptomatic HSV viremia. Likewise, HSV infection does not usually recur after 1 year of acyclovir treatment. Here, we have a child presenting with what seems to be recurrent congenital HSV infection even with adequate treatment. These atypical HSV presentations may have been due to NK cell deficiency. We, therefore, propose that clinicians should consider NK cell deficiency as possible etiology when HSV presents in an atypical manner as described in our case.