Background: elevation of body temperature is common in postoperative children as an inflammatory reaction to surgical incision prompts the mothers need for support by proper knowledge and practice. Aim the aim was to evaluate the effect of nursing educational sessions about fever on the knowledge and practices of mothers at the pediatric surgical unit. Design one group pre-posttest quasi-experimental research design Sample: A convenience sample of 100 mothers of children admitted to the pediatric surgical unit in Cairo University Specialized Pediatric Hospital for 6 months. Setting: the study conducted at Cairo University Specialized Pediatric Hospital (CUSPH) in the right side of pediatric surgical unit on the fourth floor. Tools: Structured interview questionnaire, observational checklists for axillary temperature, and cold compressors developed by the researcher. Results: there were a statistically significance difference between the total mean scores of mothers' knowledge and practice before and after the educational sessions and at the time of discharge. Also, there was a statistically significant correlation between mothers' knowledge and level of education and place of residence in addition to significant statistical correlation between mothers' axillary temperature practice and level of education. Conclusion: the current study concluded that mothers who receive nursing educational sessions about fever have a higher mean score of knowledge and practice than before. Recommendations: emphasize the importance of education provided for mothers including knowledge and practice to improve their knowledge and performance regarding fever care.