Abstract： Infantile malignant osteopetrosis (IMO) is a rare congenital disease that is characterized by an impaired function or differentiation of osteoclasts.IMO is the most severe type of osteopetrosis.Patients usually present various fatal manifestations soon after birth and die in infancy or childhood.Clinical features include bone marrow failure resulting in pancytopenia,hepatosplenomegaly,blindness secondary to optic nerve compression,hydrocephalus,and other neurological complications.[1] T-cell immune regulator 1 (TCIRG1,Gene ID:10312) is one of the main genes that are responsible for the majority of IMO cases.Mutations in TCIRG1 associated with general clinical features have been reported in some studies.[2] In this study,we reported the ocular manifestations and genetic findings of an IMO patient.