INTRODUCTION:Patients with recurrent wheezing should be evaluated for asthma and the differential diagnosis should be made carefully. The aim of this study was to evaluate the demographic and etiological characteristics of patients presenting with recurrent wheezing under 3 years of age. METHODS: Ninety-two wheezy children were consequently enrolled in this study at the outpatient clinic of Dr Sami Ulus Maternity, Children's and Diseases Training and Research Hospital, Ankara, Turkey between March 2009 and March 2010. Demographic characteristics, number of attacks in the last year, the number of hospitalizations, eosinophils were recorded. RESULTS: The mean age of 92 patients was 19.9 + -9.4 months and the youngest patient was 6 months. Seventy of the cases were male. The etiologic evaluation of the cases was as follows: 42 patients with atopic wheezing, 28 patients with gastroesophageal reflux and 23 patients with viral induced wheezing. Eosinophilia was not statistically significant in patients with presence of atopy in family members (18 patient) compared to those without familial atopy history. DISCUSSION AND CONCLUSION: In our study the most common etiological factor is atopy and it is followed by gastroesophageal reflux and viral agents, respectively. The definition of wheezing children includes diseases with different pathophysiology, course and prognosis. Children with nonatopic wheezing may develop chronic inflammation in the lungs similar to asthma. It is necessary to differentiate these diseases in the early period and to make the follow-up and treatment approaches correctly. Produced from the thesis titled ''Is there a diagnostic value of high-sensitivity C-reactive protein in wheezing infants?''.