Background: Various animal and human studies have demonstrated that airway pressure release ventilation (APRV) may have advantages over conventional ventilation in the management of acute respiratory distress syndrome (ARDS); however, it is still not used consistently because of the few studies in this regard.Aim of the work: The aim of this work is to compare outcomes of APRV in patients with ARDS with synchronized intermittent mandatory ventilation (SIMV) where positive end expiratory pressure (PEEP) is used.Patients and methods: the study included (50) patients with ARDS, they were randomly divided into two groups, group (A) patients were given APRV pattern, and group (B) patients were given (SIMV+PEEP). Data were obtained before and throughout the period of mechanical ventilation and up to 60 days. Changes in arterial blood gases, hemodynamics and LIS and outcome measures were compared in both groups.Results: demographic and baseline clinical data were similar in both groups with no differences. Follow up data showed that APRV was associated with better oxygenation, less ICU length of stay, more ICU-free days, less ventilation days, more ventilator free days and more sedation free days in comparison to SIMV+PEEP (p>0.05). However, there were no significant differences between groups regarding mortality, length of hospital stay and rates of tracheostomy and successful extubation (p<0.05). Conclusion: In comparison to SIMV+PEEP, APRV can significantly improve oxygenation, decrease need for sedatives, increase free ventilation days and shorten duration of ICU stay; however, APRV has no advantage over SIMV+PEEP regarding mortality.