Background: Acute respiratory tract infections (ARIs) constitute the major causes of mortality and morbidity among under‑five children of the developing world. The prevalence of ARIs is determined individually or collectively by a number of factors which may be prevalent in our environment. Aim: The present study is aimed to determine the risk factors that affect the prevalence of ARIs in under‑five children in Enugu. Subjects and Methods: A cross‑sectional study of 436 under‑five children diagnosed with ARI was carried out in three hospitals in Enugu. Participants were consecutively enrolled after being diagnosed as a case of ARI. Structured pro foma was used to collect sociodemographic characteristics, anthropometric data and risk profile. Data were analyzed using Epi info version 6.0 and significant probability value was 5%. Results: A total of 436 patients were enrolled for the study 224 males and 212 females M: F 1.06:1. The mean age of the population was 18.75(13.38) months and there were 31.6%(138/436) cases of pneumonia 6.9%(30/436) cases of bronchiolitis and 61.5%(268/436) cases of acute upper respiratory tract infections. Children less than 20 months accounted for 60.9% (84/138 cases) of pneumonia, 86.7% (26/30 cases) of bronchiolitis, and 64.5% (173/268 cases) of acute upper respiratory tract infections. Pneumonia was noted in about 75.7% (56/74) of inadequately nourished children compared to 22.6% (82/362) in adequately nourished children. Other risk factors identified in the study include inadequate breast feeding, poor immunization statues, attendance to daycare centers, large family size, poor parental educational statues, parental smoking, living in the urban area and use of biofuels. Conclusion: ARIs are affected by socio‑demographic and socio‑cultural risk factors, which can be modified with simple strategies. It is recommended that control program for ARIs should be multifaceted with a strong political will.