The purpose of this report is to describe 29 cases of phakomatosis including 18 cases of tuberous sclerosis (Bourneville) and 11 cases of neurofibromatosis (von Recklinghausen) observed over a 10-year period at the Neurology Department of the University Hospital Centre in Conakry, Guinea. Findings during this period were consistent with those classically reported in the literature: high frequency of advanced skin lesions coalescing into massive tumours, occurrence of seizures of all types and development of a wide variety of complications as a result of late diagnosis. Our experience underscores the need for follow-up and surveillance of these patients by somatic studies based on neurological, ophthalmologic and tomographic data depending on clinical findings.