This study concerns the evolution of consanguinity in Morocco in its historical, religious, legal, and sociological context with regards to Moroccan customs and undertakes to evaluate its relationship to public health. Thus it attempts to specify if consanguinity, in its present state in Morocco, poses a problem for public health. With this goal in mind, methodology has been concentrated on two approaches. The first, based upon examination of documents and oral research interviews, has made theoretical assessment possible. The second, substantiated by the study of notarial marriage acts and the analysis of 4773 medical files concerning consanguineous marriages compiled throughout the seven regions of Morocco, has enabled us to specify the importance and the evolution of consanguinity and its impact on health. This study shows a marked decrease in consanguineous unions predominantly found in rural and mountainous zones and frequent between first cousins, especially the paternal cousin. From the medical standpoint, our study has revealed the absence of pathology in 97.13% of cases studied, the transmission of various gifts in 1.08% and that of degenerative traits in 1.79% of the descendants. Consequently, in our country, a country in perpetual evolution and in contact with the outside world, consanguinity which is disappearing of its own accord does not present a preoccupying problem for public health. Its future would seem to be limited to the relation between the physician and marriage partners in search of genetic counsel.