Background: Mechanical ventilation is often lifesaving but is associated with serious complications, in part because it is delivered to patients at high risk of lung or cardiac compromise. These complications may be related to the direct mechanical effects of the intrathoracic pressures generated by the ventilator, to alveolar and systemic inflammation, or to neural stimulation. The aim of study to assess the clinical profile and outcome of children treated with invasive mechanical ventilation. Patients and methods: An Observational study conducted on 74 patients in PICU in Pediatric Hospital ,Faculty of Medicine, Zagazig University, all patients are intubated and connected on mechanical ventilators, all patients underwent a thorough medical history examination,(Patients' data) were collected including demographic data as age and sex, diagnosis, length of stay on MV from the time of initiation to the time of liberation, mode of MV used upon its initiation, complication,( outcomes and its relations to cause of ventilation and admission ,comorbidity ,mode of MV, age and duration of weaning and all MV parameters). Result: Outcome of mechanical ventilation among studied group showed14.9% have bad outcome and 85.1% had good outcome, also showed that Pneumonia was significantly associated with bad outcome.Conclusion: The results of the present study show a significant number of preventable adverse events, especially atelectasis and ventilator associated pneumonia. Prolonged duration of ventilation was significantly associated with complications as well as mortality related to mechanical ventilation, also APRV mode has significantly association with bad outcomes.