Considering G6PD deficiency, especially in the Northern regions, and its association with neonatal icter and related complications, and the fact that no study has been conducted in Iran in terms of the relationship between enzyme-associated specific DNA mutations and clinical manifestations in neonatal age group, the present study aimed to investigate three common G6PD gene mutations in Mazandaran Province in neonatal age group and its association with the incidence and the severity of neonatal icter.