Background: Pneumonia is still a major cause of death and incurs significant morbidity and mortality in developing countries. Thus, patients care does not only focus on treatment but also identifying factors that associated with the patient's outcome. Therefore we defined factors associated with mortality in pediatric pneumonia and assessed the outcome of pneumonia supported by mechanical ventilation in children. Methods: We performed cohort retrospective study by collecting data of pediatric pneumonia patients who admitted to Pediatric Intensive Care Unit (PICU) at Dr. Sardjito General Hospital, from 2014 to 2016. Chi square and multivariate logistic regression tests were used to analyze the variables: anemia, comorbidities, bacteremia, age between 1-6 months old, and underweight as associated factors for mortality. Results: One hundred and eleven children were included in this study. Those patients were diagnosed as community acquired pneumonia (79.3%), hospital acquired pneumonia (14.4%) and ventilator associated pneumonia (6.3%), with mortality rate 47.7%. Multivariate logistic regression analysis revealed that bacteremia, and underweight could be used as predictor factors of mortality for pediatric patients with pneumonia who were supported by mechanical ventilation with OR 2.5 (CI 95%: 1.03-6.1) and 2.4 (CI 95%: 1.1-5.7), respectively. Conclusion: Factors associated with mortality for pediatric patients with pneumonia who were supported by mechanical ventilation were bacteremia and underweight. It is necessary to compare our findings with other centers.