10312 persons were selected randomly from attendants of outpatients clinics of central hospitals located in Ten centres in Dakahlia Governorate. The diagnosis of schistosomiasis was ascertained by clinical manifestation and laboratory findings [Urine, Stool and I. D. T. ]. The over – all prevalence of infection obtained using I. D. T. was 73. 02% while by direct methods it was 48. 13%. The highest rate of infection was recorded in those aged 10 to 20 years 67. 45%. The infection rates were higher in males than females and the highest prevalence of the total infection was among the fishermen, boatmen and farmers. The prevalence of infection regarding the administrative centres varies from one centre to another. The infectivity rate of snail vectors depend upon the age of snails, water temperature and water pollution