Abstract: Objective: To investigate the relationship of the related factors, clinical characteristics, prognosis and severity score of neonatal thrombocytopenia(NT) . Methods: Eighty-nine infants with NT were collected in neonatal intensive care unit, these patients were divided into mild group and severe group. The related factors, treatment, prognosis and relationship with the severity score were analyzed. Results: Compared with mild group, the recovery time of platelet in severe group was prolonged(P ＜ 0. 05) , red blood cell count and severity score were decreased, C reactive protein and incidence of were increased, there were significant differences(P ＜ 0. 05-0. 01) . Conclusions: Infection is the key factor of NT, there is very close relationship between the level of platelet and severity score. Early diagnosis and treatment is very crucial, and most patients have a favorable prognosis.