Objective To investigate the clinical value of bedside cardiac ultrasound results in the early diagnosis and prognosis of neonatal pulmonary hemorrhage (NPH). Methods From January 2020 to May 2023, 24 neonates diagnosed with neonatal pulmonary hemorrhage in Nanchong Central Hospital were selected as the pulmonary hemorrhage group. At the same time (admission time<=1 month), 48 matched non pulmonary hemorrhage neonates of the same gestational age (birth age<=1 week) were selected as the control group. The clinical data and cardiac ultrasound results of the two groups of neonates were collected and analyzed, retrospectively. Results Comparison of left ventricular end-diastolic volume (EDV), LV end-systolic volume (ESV), stroke volume per volume (SV), left ventricular ejection fraction (LVEF), short axis shortening rate (FS) of the left ventricle in the pulmonary hemorrhage group and the control group， there was no significant difference (P> 0.05). The pulmonary artery pressure and arterial catheter diameter in the pulmonary bleeding group were significantly greater than those in the control group (P<0.05). Left ventricular end-systolic volume (ESV) and pulmonary artery pressure in the term middle pulmonary hemorrhage group were greater than that in the control group (P<0.05). The left ventricular ejection fraction (LVEF), left ventricular short axis shortening rate (FS), pulmonary artery pressure, and arterial catheter diameter were all greater than those of the control group (P<0.05). Area under the curve of pulmonary artery pressure, catheter diameter and combined prediction of NPH (area under curve, AUC) were 0.789,0.677, and 0.794, respectively. Pulmonary artery pressure was more predictive of NPH than arterial catheter diameter, The two combined prediction was better than the individual prediction. ACT diameter was positively associated with poor outcome of NPH (OR=3.075,95%CI:1.177~8.035).Conclusion NPH before term cardiac function changes to pulmonary artery pressure with left heart output decrease as the main performance, and premature infants before NPH to arterial catheter diameter increase as the main performance, accompanied by pulmonary hypertension and compensatory cardiac output increase. Pulmonary artery pressure has certain value for early prediction NPH. Arterial catheter diameter for NMH prognosis has certain value