objective: to verify the prevalence of anemia associated with the introduction of complementary food in children less than two years old in the city of campinas, s？o paulo, brazil. methods: a cross-sectional survey was performed in 354 children between 6 and 12 months of age which were registered in the live births information system from campinas area. health professionals interviewed the mothers, who answered a questionnaire about food introduction and socioeconomic status. capillary blood was collected and the hemoglobin level was determined by hemocue？. anemia was diagnosed if hemoglobin level was below 11g/dl. survival analysis was performed to determine the influence of complementary food introduction on anemia. results: 66.5% of the children had hemoglobin levels lower than 11g/dl. anemia was associated to early introduction of the family diet (p=0.036), bread (p=0.012), yogurt (p=0.006), soft drinks (p=0.005), candies (p=0.005) and snacks (p=0.013). conclusions: inadequate complementary food introduction is associated with anemia. this information should be addressed by health programs in order to prevent anemia in children.