Background: When Doppler echocardiography is not readily available, a biomarker like NT-pro-Brain Natriuretic Peptide (BNP) can be used to diagnose patent ductus arteriosus (PDA) in premature infants. Objective: To evaluate the diagnostic accuracy of the cardiac biomarkers BNP for detection of hemodynamically significant patent ductus arteriosus (hsPDA) in preterm newborns and their correlation to echocardiography results. Patients and Methods: At tertiary care hospital at National Heart Institute, a total of 46 premature neonates (< 34 weeks gestation) or those whose birth weight was less than 1200 g who were admitted to Neonatal Intensive Care Units (NICUs) were included in this cross-sectional study. Patients with PDA were classified as having either hsPDA or non-hsPDA based on a large ductal flow with left to right shunt on colour Doppler echocardiography, and all participating neonates underwent this evaluation between 48- and 72-hours following birth. Results: Serum brain-type natriuretic peptide was statistically significantly higher in cases with hsPDA. Serum brain-type natriuretic peptide statistically had significant high diagnostic performance in predicting hemodynamically significant patent ductus arteriosus. Serum brain-type natriuretic peptide at cut-off value of ≥108.0 pg/mL, had moderate sensitivity, but high other characteristics in diagnosing hsPDA. Conclusion: Preterm newborns at risk for poor outcome due to PDA may be identified by serum brain-type natriuretic peptide in combination with echocardiography.