Osteopetrosis (also called Albers-Schoberg's disease, Marble bones and chalk bones) is a rare hone dysplasia in which, on the basis of a failure of osteoclastic and chondroclastic resorption, the bone become exceedingly dense. Two clinically distinct forms are now recognized and have different patterns of inheritance. The milder form is transmitted as an autosomal dominant trait and the more severe form is transmitted as an autosomal recessive trait. We have experienced a familial osteopertrosis, mother and three siblinges out of six, which was thought to be a autosomal dominant inheritance. We report a case of milder form of osteopetrosis with a review of literature.