This work is a thesis submitted to the High Institute of Public Health-Alexandria University in partial fulfillment of the requirements for the degree of Doctor of Public Health Sciences (Parasitology and Medical Entomology). It is a trial to confirm the presence of the two species of Fasciola (F. hepatica and F. gigantica) in Egypt and to define the species incriminated in human fasciolosis. Proper identification and characterization of Fasciola species present in Egypt is very important to build up a powerful strategy of control, which may be applicable to other countries.