Background: Acute pulmonary edema (APE) is one of the main diagnoses for dyspnea patients in emergency departments (ER). High-velocity nasal cannula (HVNC) might be considered as an alternative support for early management of APE in the ER. Objectives: to compare the effectiveness of HVNC therapy for those with APE to that of conventional oxygen therapy (COT). Methodology: This study was a randomized controlled trial with 60 APE patients admitted to the critical care and chest units at Beni-Suef University Hospital. We randomly assigned patients to Group A, who received COT. Group B received HVNC. All patients received a full history and evaluation, a chest X-ray, and a chest CT scan. A complete blood count (CBC), coagulation profile, renal function tests, and assessments of serum sodium, potassium, and arterial blood gas (ABG) were included in laboratory examinations. We conducted these tests at admission and again six hours later. Results: We linked the use of HVNC to a significant drop in respiratory rate. Both groups' PO₂ levels increased while PCO₂ decreased. The HVNC intervention was more effective in increasing PO₂ and decreasing PCO₂ levels than the COT. There was a trend in the HVNC group toward less reliance on mechanical ventilation (MV) as compared to COT. The length of time patients spent in the ICU dropped significantly for those receiving HVNC.  Conclusion: In patients with APE, HVNC significantly improves ABG, ICU stay duration, and MV frequency compared to COT.