Background: Mechanically ventilated patients are at high risk of developing pulmonary complications, which can prolong hospitalization and increase morbidity. Implementing a structured nursing intervention protocol is essential to improve patient outcome and prevent complications such as ventilator-associated pneumonia and pulmonary barotrauma. Aim of the study: Evaluate the effect of implementing nursing intervention protocol on reducing selected pulmonary complication among mechanically ventilated patients. Research design: Quasi - experimental research design (study & control) was utilized to fulfill the purpose of this study. Subjects: A purposeful sample of 80 adult mechanically ventilated patients (MV) was assigned in the current study, which started with the initiation of the MV connection. Setting: The current study was conducted at the following critical care units (Chest intensive care unit and Intensive Care Unit) affiliated to Cardio-thoracic Surgery Hospital and Main Minia University Hospital in Minia City, Egypt. Tools of data collection: One tool was utilized in the current study; it contains five parts. First part: Patient's Demographic Characteristic, Second part: Medical Data. Third part: Hemodynamic Parameters Assessment. Fourth part: Respiratory Parameters Assessment Fifth part: Nursing Intervention Protocol. Results: the current study results showed that 7.5% & 6% of the study group post-nursing intervention protocol compared with 19% & 15% of the control group receiving routine hospital care had ventilator-associated pneumonia and barotrauma complications, respectively, with a highly statistical significant difference between both study and control documented with p-value (0.014, and 0.004), respectively. Implementation of nursing intervention protocol have a direct effect on mechanically ventilated patient's outcomes and minimizing selected pulmonary complication among study group. Conclusion: Based upon the results of this study, it could be concluded that, implementation of nursing intervention protocol for mechanically ventilated patients had beneficial effect on reducing the incidence of selected pulmonary complications among study group compared to the control group. Recommendations: nursing intervention protocol should be incorporated as a part of routine care of ventilated patients in ICU, designing a comprehensive checklist to improve nurses' compliance with nursing structured nursing intervention protocol to prevent pulmonary complication.