Background: Echocardiography is non-invasive technique that used to image the effects of pulmonary hypertension on the heart and estimate Pulmonary Artery Pressure from continuous wave Doppler measurements. Pulmonary hypertension prevalence of about 1 - 10% of the global population. Severe persistent pulmonary hypertension is about 2-6 / 1000 of all births. Female/Male ratio is about 2/1. The symptoms of pulmonary hypertension include respiratory distress, poor feeding, Cyanosis and others. Aim: The current study aimed to assess the incidence of pulmonary hypertension in newborn infants in NICU using Echocardiography. Patients and Methods: The current study is a case control study & aimed to estimate the prevalence of pulmonary Hypertension in newborn infants in the NICU in Al-HussainUniversityHospital during the period from May 2016 till April 2017. The newborn infants were subdivided into four groups according to the gestational age. Group (A): 15 apparent healthy babies who were collected from Obestetric and outpatient departments. Group (B): 15 babies who were admitted to NICU due to underlying problem. Group (C): 30 Near-term infants from 32 – 36 GA. Group (D): 30 Preterm infants less than 32 GA. Including all babies from both sexes, aged 0-14 days, any gestational age and evaluated with Echocardiography. Babies with congenital anomalies, weight less than 1000gm and GA less than 30Weeks were excluded. Results: The demographic data showed no differences between all groups regarding age and sex. Many risk factors were observed during the study as respiratory distress syndrome (16.7%), premature rupture of membrane (10%), maternal diabetes (5.6%) and meconium aspiration syndrome (8.9%). Pulmonary hypertension ^(P++) occurred commonly in females (60%), with RDS (33.3%) and with cesarean section (80%). All cases with P⁺⁺ were in need to oxygen supplementation (100%) with O2 saturation ranging from 93-100% and the blood gases analysis tended to be metabolically acidosis. Finally we found the prevalence of pulmonary hypertension in our study were 5.6% of all cases with mean systolic artery pressure 51.80±10.73 mmHg and the mortality rate reached up to 20%.