Background & Objectives: Giardiasis is one of the parasitic infections in the gastrointestinal tract which caused by flagellate protozoa that called giardia and it causes diarrhea. Giardia cysts defecate from infected people. These cysts can enter the body through contaminated hands, water, and food products. Diarrhea, weight loss, abdominal pains, growth failure, malabsorption of carbohydrates, fats and vitamins are the giardiasis symptoms.

Methods: In this study, samples were taken from 203 people that were working in different food supply and distribution centers in the South Pars petrochemical. After sampling, samples were analyzed according to standard procedures. The results of examinations were studied after verification them by laboratory chief and their related physicians.

Results: Out of the whole examined people in this study, kitchen (28%) and salad maker (14%) centers were the maximum and minimum population, respectively. 8.87% of the total populations were infected by giardia, which salad making center had the greatest share. As well as, the rate of infectious by giardia among the administrative and dishes washing centers was the lowest.

Conclusion: Education level and personal hygiene such as hand washing with a detergent can be important in reducing infection due to giardia. So, the training of workers and also periodic testing of individuals can reduce these pollutants.