Acute respiratory infections (ARIs) are the single greatest cause of death among children throughout the world. They are responsible every year for the deaths of 4.3 million children under 5 years of age worldwide. Community- or hospital-based surveys for finding out the prevalence and various factors associated with ARI are very few, especially in urban areas. Also, surveys to study the use of vaccines in preventing ARIs are scarce. Hence, we studied ARI in children aged 1 year to 5 years in a tertiary care hospital in Kerala. The aim was to determine the frequency of ARIs in the last 1 year in children aged 1 year to 5 years, attending the immunization clinic at Lourdes Hospital, Kochi, and assess the selected epidemiological, socio-demographic, nutritional and immunization factors associated with ARIs in the study group. Children attending the immunization clinic at a tertiary care hospital, Kochi, in the age group of 1 year to 5 years were selected. A brief introduction was given to the mother/caregiver of the child regarding the purpose of the study and was asked to fill out the questionnaire. Informed consent was taken. For the study, ARI is defined as the presence of one or more of the following: cough, running nose, blocked nose, sore throat, difficulty breathing, or ear problems; with or without fever. Results were analyzed. Mother was the caregiver in 67% of the cases. When the caregiver was the mother, ARI is found to be less. Among those mothers who had no formal education, 100% of their children got ARI. Children whose caregivers were 30 years and older had lesser ARI. The proportion of children with ARIs was more with a history of respiratory infection among family members (parents/siblings) compared to those with no such history. The occurrence of ARI was more frequent in rural compared to urban areas. There is a significant proportion of ARI in non-exclusively breastfed infants, bottle feeding, and early initiation of complementary feeding. Children with a history of exposure to cigarette smoke had an increased occurrence of ARI. Similar results followed for exposure to biomass fuel and exposure to cold and rain. Children who were not immunized to vaccines-pneumococcal, Hib, measles, vitamin A, showed a higher occurrence of ARI compared to immunization. The studies regarding factors influencing ARI are relatively rare in an urban setting, thus this calls for more studies in urban areas. Health education can change the healthcare-seeking behavior and attitude of parents for preventing ARI-related deaths. Family physicians can play a significant role by educating caregivers of children and giving timely services. Promoting and ensuring exclusive breastfeeding practices, timely weaning after 6 months, and avoidance of bottle feeds can dramatically decrease the episodes of ARI.