Rapidly involuting congenital hemangioma (RICH) is a rare vascular lesion, identified in 1996, of elective localization in the dermal-hypodermic tissue. Its name comes from its particular natural course: it is fully developed at birth and then completely involutes, usually in the first year. We present a case of a RICH of the scalp discovered with a screening ultrasonography in the 31st week of gestation. We list the differential diagnoses. After birth, positive diagnosis lies preferably on pathology examination of a biopsy specimen in order to eliminate the hypothesis of a less favorable vascular lesion, teratoma or malignant tumor.