The hospital-acquired pneumonia is the most frequent cause of death and is associated with mortality rates up to 30%. Aim: The aim of the present study was to explore the degree of compliance with the protocol on the prevention of VAP by nurses in ICU. Material and methods: The studied sample consisted of 164 nurses (response rate 76.6%) working in ICU of nine (9) Hospitals in Attica. For data collection it was used a special designed questionnaire. Data analysis was performed by the statistical package SPSS ver. 15. Results: 25.6% (n = 42) of the sample were men. 43.9% (n = 72) had experience in ICU <5 years, 30.5% (n = 50) 6-10 years and 25.6% (n = 42) 11-15 years. The compliance rate of the sample with the instructions of the protocol on the prevention of VAP was 69.3 ± 17.2%. Men complied significantly more (69.3 ± 17.2%) than women (68.5 ± 18.2%) (p <0.001). Nurses with less experience in ICU complied significantly less than the others (p <0.001). The compliance of the respiratory ICU nurses was significantly greater than in other ICUs (p <0.001). Conclusions: The compliance rate for ICU nurses with protocols to prevent VAP is satisfactory. The role of nurses in the prevention of VAP is very important and can help reduce morbidity, mortality, length of patient stay in hospital and reduce health care costs.