Hereditary spherocytosis (HS) is a congenital disease in which erythrocyte membranes are abnormal, with ANK1 defects as the main cause. The diagnosis of neonatal HS is difficult due to poor phenotypic specificity. Therefore, a detailed inquiry into family history may be helpful for diagnosis. Here, we describe a familial case of HS caused by a novel mutation in ANK1. The proband is a premature infant of Chinese Han ethnicity characterized by progressive aggravation of anemia and jaundice. The disease was caused by a frameshift mutation (c.3392delT/p.Leu1131Argfs*15) of ANK1 that was identified by genetic testing. In vitro functional experiments showed that this variant may seriously affect the protein expression and further expanded the mutation spectrum of ANK1-HS. In this case, we emphasize the diagnostic value of early-intervention genetic testing for neonatal hemolytic anemia with a family history.