Rickets is a rare child disease especially in developed countries. Nutritional rickets remains the most prevalent condition, although congenital forms are well known. In the latest group, vitamin D dependent rickets type II is the rarest form and it can course with or without alopecia. There is a mutation on the receptor for vitamin D, with peripheral resistance to the vitamin D action. The authors present two clinical cases of vitamin D dependent rickets type II, in which the alopecia was a peculiar clinical sign that allowed the diagnoses. With prolonged calcium infusions, we achieved normal seric levels of calcium and correct bone disorders; alopecia persisted. This treatment is the most effective way to control the disease.