Introduction: Pneumonia Associated with Mechanical Ventilation (VAP) is a lung infection that appears 48 hours after the patient is on ventilatory support and can be prevented if the recommended measures are applied. Objetive: To determine the Knowledge and Practices of VAP prevention in personnel of ICU nursing in 3 hospitals in Nicaragua, during the II Semester 2022. Methodology: Cross-sectional descriptive study with a quantitative approach A questionnaire was applied to identify knowledge and a checklist to identify practices in relation to VAP prevention measures The sample It was made up of 43 ICU nursing workers. The analysis was carried out with Microsoft Excel 2019 and the SPSS 20 program. Results: The female sex predominates with 58 1%, the majority aged between 25-34 years, 32 6% of the staff affirm that they receive information and training for the prevention of VAP IE 86% of the nursing staff know the five moments for the hand hygiene, 74.4% are unaware of the value of the accumulating preston and in practice 76.7% do not carry out its verification only if it is insufflated. 95.3% perform oral hygiene with 0 12% clorhexidina. 85% do not wash their hands after contact with the patient Conclusion: Nursing staff have gaps in knowledge about VAP prevention, which has an impact on practice. It seems that years of experience do not produce changes in VAP prevention knowledge or practices in critically ill patients Keywords: Ventilation pneumonia, nursing care.