A total of 110 stool samples from out and in-patients from different areas in Great Cairo suffering from diarrhea were examined for parasitic causes. Stool samples were subjected to the direct wet smear method and Sheather's sugar flotation and stained with Giemsa and/or modified Ziehl-Neelsen. Also, stool samples were cultured on agar plates for strongyloidiasis. The overall parasitic infection rate was 60.9% and non parasitic cause was 39.1%. The parasitic infection rate in a descending order was 31.1% for Cryptosporidium parvurnm, 19.8% for Giardia lamblia, 9.9% for Entamaeba histolytica and lastly 1.8% for Strongyloides stercoralis. The main clinical presentation of diarrheic patients in a descending order was vomiting (31.3%), dehydration (29.86%), abdominal pain (29.86%), flatulence (26.86%), anorexia (23.89%), tenesmus (17.9%) and lastly fever (4.47%). The risk factors were living in rural areas, education level, contact with farm animals and/ or pet animals. However, most of these risk factors although showed high percent, yet they occurred in patients with other causes of diarrheas. Artificial breast feeding was not evaluated as only 3 infants had C. parvum compared to non parasitic cause in 1 on the breast feeding.