Background: Nosocomial infections (NIs) are considered the major and common healthcare problems in most healthcare settings at most of developing countries like Iraq, important to assess the nurses' knowledge level and identifying gaps of their knowledge about NIs. Objectives: To assess the nurses' knowledge about nosocomial infection, and to find out the relationship between nurses' knowledge about nosocomial infection and selected demographic variables. Methodology: A descriptive study was conducted at burns' centers and units in the middle Euphrates teaching hospitals. The study was carried out from (25th October 2017) to (1st June 2018), A purposive (non-probability) sample was selected (129) from nurses that working at burns' centers and units in the middle Euphrates teaching hospitals. The instrument was presented to (15) experts from several universities to be valid, the reliability of the instrument was determined through the implicated the Cronbach's Alpha, the reliability of this instrument was (r = 0.833). Results: The result of study was showed that the majority (69.8%) of nurses had (passed score) of knowledge regarding nosocomial infection in burns'units at middle Euphrates teaching hospitals.in addition, the present study pointed out there was a significant relationship between nurse knowledge and number of training courses about nosocomial infection. Conclusion: Nurses were pass knowledge in terms of nosocomial infections, prevention, control and precaution in patient care. Nurses age, gender, education, years of experience in-out burn unit have been not influenced their knowledge. Number of Nurses training courses have been affected their knowledge.