Anemia is a frequent manifestation and an important health problem. The aim of this study was to found the prevalence of anemia among primary schoolchildren and determine the risk factors associated with anemia. The study group was composed of 1531 students between 6 and 16 years old from 14 primary schools located in seven different regions of Istanbul. Data were collected via a questionnaire filled out by parents. For all students, a complete blood cell count detected by an automated cell counter and anemia prevalence was determined according to Dallman criteria. The overall prevalence of anemia was found to be 27.6 per cent. There was no significant relationship between the prevalence of anemia and the students' age, gender, parents' educational level and employment, and monthly family income by logistic regression analysis. Only the number of family members and malnutrition were risk factors for anemia. Today, anemia is a common problem among primary schoolchildren in Istanbul. Identification of the risk factors is essential for the prevention of anemia.