Introduction: Infection control or hospital-acquired infections are the major concern of the health care system and agencies. Critical care nurses are on the first-line contact with the patients, so on, they are most vulnerable to acquired infections. It is really important to regularly check their knowledge and practices concerning infection control. Objectives: The study aims to identify the impact of years’ experience on nurses’ knowledge and practices concerning infection control in three hospitals and center (Baghdad teaching hospital, Ibn Al-Nafees hospital, and Ibn al-Bitar center) Methodology: Cross-sectional study was conducted, the study starting from 4th of July 2020 to 13th of November 2020. Non-probability (purposive) sample was used to select 110 nurses who work at critical care units in three hospitals and center (Baghdad teaching hospital, Ibn Al-Nafees hospital, and Ibn al-Bitar center). The years of experience should no less than one year. The instrument was composed of two parts. Firstly, covers the nurses’ demographic characteristics. Secondly, included self-report questions about nurses’ knowledge and an evaluation sheet concerning nurses’ practices of infection control with 24 questions for knowledge and 12 questions for practices checklist. Results: The study revealed that the nurses’ knowledge toward infection control record 38%, 41%, and 21% for low, moderate, and high knowledge respectively. In comparison, nurses practices record 47%, 42%, and 11% for low, moderate, and high practices respectively. Most of the study sample 62% was females while 38 % of the subject was males. The age group (20-29) takes the highest percentage (38%), In addition, about (27.3%) of the nurses who works in critical care units have 1-5 years of experience. Significant statistical associations were found between nurses knowledge and practice from one hand and years’ experience on the other hands p ? 0.05. Recommendation: Based on this finding, the researcher recommended further studies involve more nurses and other health professionals regarding infection control and highlight the importance of infection control to nurses with (1-5) years’ experience by symposium or teaching programs.