Background: Fever is a common problem in ICU patients; it is a medical condition when there is an uncontrolled rise in the body temperature, measured as above 37.5 degrees Celsius. Aim of the study: This study aimed to assess nurse's performance regarding patients with fever at intensive care units. Study design A descriptive exploratory design was used in this study. Setting intensive care units at Nasser General Hospital, affiliated to Ministry of Health. Study subject: A convenience subject of all available nurse's Tools: I Self -administration questionnaire, II nurses' practice observational checklist, III-Nurses' attitude rating scale. Results: revealed that the mean age of the studied nurses were 26.1±4.4, 62.9% of the studied nurse's had satisfactory level of knowledge, there was 75% of them had satisfactory level of practices and 55.7% of nurses under study had positive attitude toward patients with fever at intensive care units. Furthermore, there was a positive correlation between attitude and their practices, there is a statistically negative correlation between knowledge and attitude of studied nurses regarding patient with fever at intensive care units. Conclusion: More than two thirds of the studied nurses had satisfactory level of knowledge, three quarter of them had satisfactory level of practices regarding patients with fever at intensive care units, and more than half of the studied nurses had positive attitude toward patients with fever at intensive care units. Also, there is high significant relation between nurses' knowledge, practice & their demographic characteristics. Recommendations: in service training program must be developed based on nurses' need assessment regarding care of patients with fever.