Purpose: The iam of this study was to investigate the effect of healthcare associated infections (HAIs) and broad spectrum antibiotic use in newborn period on asthma, allergic rhinitis and atopic dermatitis Material and Methods: Seventy three children treated for HAIs in newborn period in Neonatal Intesive Care Unitin a 6 years period, and their 41 siblings who were healthy in newborn period were included in the study. Parents answered a detailed questionnaire, children were examined and complete blood count, serum total Ig E and specific Ig E levels were studied Results: Ventilator associated pneumonia was observed in 32 (45.2%), blood stream infection in 28 (38.4%) and clinic sepsis in 12 (16.4%) of 73 children with HAIs. Asthma was significantly higher in HAIs group compared to sibling group (32.9% vs. 4.9), whereas there was no significant difference in allergic rhinitis (4.1% vs. 2.4%) and atopic dermatitis (6.8% vs. 0%) among groups. When nonallergic 85 subjects and allergic 29 children compared, children who had been hospitalised and treated with broad-spectrum antibiotics in newborn period were almost 11.5 times as likely to have an allergic disease Conclusion: Asthma was significantly higher in HAI group, and allergic disease risk seems to increase in children treated with broad-spectrum antibiotics for HAIs in newborn period