Background and objectives Pneumonia is the most common cause of death in children under five years of age. Epidemiological factors and the disease burden differ in developing and industrialized countries. The present study is a cross sectional observational study, carried out from August 2018 to August 2020 in Hindu Rao Hospital, to assess the prevalence of congenital heart disease (CHD) in patients with pneumonia in children up to 5 years. The main objectives of the study were to study the prevalence of congestive cardiac failure (CCF) in pneumonia with and without congenital heart disease. Material and methods Patients under 5 years of age, presenting with pneumonia during August 2018 to July 2020 were enrolled for study. The bio-data of each patient was documented each patient was clinically evaluated thoroughly and findings noted. Pneumonia was diagnosed on typical history, physical findings, blood investigations and chest radiographic finding of pneumonia infiltrates in either one or both lung fields. All the cases of pneumonia underwent transthoracic 2 Dimensional (2D) and Doppler echocardiography, done by the cardiologist. Any congenital heart disease so found was noted. The type and size of the defects was documented. The ventricular septal defects were classified based on the site and size. The size of the patient ductus arteriosus was also determined. These measurements were taken to evaluate the impact of defect size on pneumonia. CCF was diagnosed when the patient fulfilled the clinical diagnostic criteria of heart failure. All the cases of pneumonia underwent transthoracic 2 Dimensional (2D) and Doppler echocardiography for diagnosis of any congenital heart disease. Results Mean age of the children with pneumonia was 9.94 months with 77.5% of the cases below 1 year of age. Male predominance was seen with 56.3% males to 43.8% females. Prevalence of congenital heart disease among cases of pneumonia was 12.5% while that of congestive heart failure was 27.5%. Most common CHD observed was VSD (14 cases; 8.8%) followed by PDA, ASD and TGA (4; 2.5% and 3; 1.9% and 1; 0.6% cases respectively). A significant association was observed between presence of congenital heart disease and development of CCF. Conclusion Our study demonstrates that most patients with pneumonia or recurrent pneumonia are likely to have an underlying illness at the time of pneumonia. Recurrent ALRTI often occurred in children with history of congenital heart diseases (CHD) and is also associated with Congestive Cardiac Failure. Children with CHD are more vulnerable to recurrent respiratory tract infection.