SUMMARY Objective. To identify the risk factors for acute respiratory diseases in children below 5 years age. Methods. A descriptive cross-sectional epidemiologic study of 588 hospital files of children with acute respiratory diseases. Results. The under the 12 months age children had a significative differences regard pneumonia, acute rhinopharyngitis catarrhal, pharyngitis and acute otitis media in relation to the children of 12 or older age (p < 0.05). The same differences were found in the background of breathing (bronchiolitis, acute otitis media and pharyngitis) [p < 0.05]. When it was compare the children with breast feeding for at least 6 months age according to the presence of bronchiolitis and acute otitis media there was a significant difference (p < 0.05), but the differences were higher in children under 12 months. Conclusion. The risk factors that predispose this population to develop pediatric acute respiratory illness are breastfeeding less than six months, respiratory history and age group.