The present study was carried out in Al Muthanna province through the period from June, 2017 to May, 2018. A (551) and (566) of stool samples were collect from urban and rural respectively from children under 12 years. The percentages of prevalence in urban and rural monthly changes (highest and lowest) were: Entamoeba histolytica (urban: 21.41%, rural: 23.49%, and total: 22.47%, urban: 28.12% in July, 5.0% in January, rural: 31.74% in June, and 5.0% in January). Giardia lamblia (urban: 21.41%, rural: 27.20 and total: 24.35, urban: 31.03% in June, 5.0% in January, rural: 36.50 in June, 0.0% January) and Enterobius vermicularis (urban: 12.15%, rural 21.55%, and total: 216.92%, urban: 15.51% in June, 5.0% January, rural 29.03 in July, 0.0% in January) respectively. The incidence according to the age and sex of children was: E. histolytica (10-24% in male), (18-24% in female), G. lamblia (13-12% in male and female), the highest infection at age groups (3-6), (6-9) in both sexes of the two parasites, and E. vermicularis (13-12% males and females), the most affected at age group (3-6). There is a significant effect of age and sex of incidence at (0.01). The mean ± standard deviation (SD) of hemoglobin (Hb), packed cell volume (PCV) and white blood cell (WBCs) for (20) patients and (20) control were as following: E. histolytica (Hb 9.88 ±0.455, PCV 31.61±1.359, WBCs 9.55 ±2.81), G. lamblia (Hb 9.71±0.519, PCV 31.12 ±1.549 and WBCs 7.94±1.117) and E. vermicularis (Hb 9.62± 0.423, PCV 30.84 ±1.265 and WBCs 8.22± 0.767) and control group (Hb 11.01±2.597, PCV 36.73± 0.475 and WBCs 7.41±1.179). Statistical analysis showed a significant effect of the three parasites on the level of Hb at (0.05), PCV and WBCs at (0.01).