Background: Intestinal parasitic infections including amoebiasis, blastocystosis, giardiasis, are all worldwide distribution with harmful effects, it is an important cause of morbidity and death rate in the poor countries. Objective: This study was done to collect information of the frequency of these diseases in some regions of Baghdad. Our objectives are to detect the frequency of human pathogenic parasites in some regions of Baghdad in stool samples of patients who would attend to AL-Kindy Teaching Hospital, Medical City Teaching Hospital and to determine the most common age group affected. Materials and Methods: Data were collected from Al-Kindy Teaching Hospital and Medical City Teaching Hospital, in the lab of parasitology from June 2021 to February 2022. The present study included (200) sample, which were collected from patients at different ages of both genders, samples of the study were selected randomly. Results: The results of epidemiological study showed that the total number infected with Entamoeba histolytica parasite was (129) positive samples with total percentage of (64.5%) in both of Al-Kindy Teaching Hospital and Medical City Teaching Hospital, Percentage of infective cases with this parasite in the two hospitals, were (93%, and 36%) respectively, followed by Blastocystis hominis with total number of (59) positive samples and a percentage of (29.5%). The percentage of infective cases with this parasite in the two hospitals, were (5%, and 54%) respectively, and then Giardia lamblia with total number of (12) positive samples, and a percentage of (6%). The percentage of infective cases with this parasite in the two hospitals, were (2%, and 10%) respectively. Males showed higher number and percentage of infection with E. histolytica, (85) case with percentage of (42.5%), while females were (44) case with percentage of (22%), while number and percentage of infection with B. hominis in males were (34) case with percentage of (17%), and females were (25) case with percentage of (12.5%), finally number and percentage of infection with G. lamblia in males (6) cases with percentage of (3%), equal females were (6) case with percentage of (3%). Infection highest percentage happened among age group (20-29) years with percentage of (28%), while the lowest percentage of infection occurred among age group (1-9) years, with percentage (1%), were detected in Medical City Teaching Hospital. In conclusions: Entamoeba histolytica was the most frequent parasite in our study, followed by Blastocystis hominis, while Giardia lambilia was the least frequent one. Also males were more affected than females to parasitic infections, and the most common age group affected was (20-29) years.Health education, safety of food and water must get higher to increase the knowledge of community about diseases caused by intestinal parasites.Using permanent stains, culture, molecular methods, and serological methods for detection of parasites, also making more studies including increasing in number of samples.