Postoperative care is very important phase for patient, as it can prevent or reduce the occurrence of the complications. Aim: Assess factors affecting postoperative nursing performance in the surgical units. Research design: A descriptive exploratory design. Setting: surgical units at Benha university hospitals. Subjects: Convenient samples of 75 nurses were worked at the previously mentioned setting at the time of data collection. Tools of the study: self-administered questionnaire and an observational checklist. Results: more than three quarters of the studied nurses had unsatisfactory level of knowledge, more than three quarters of the studied nurses reported that the total factors had an effective effect on their performance, about two thirds of the studied nurses had unsatisfactory level of practice, there were highly statistical significant relation between studied nurses' Knowledge and their experience, while there was statistically significant relation between studied nurses' knowledge and their job and their education, statistically significant relation between studied nurses' practice, their job, their experience and the courses which were taken, highly statistical significant relation between factors affecting nursing performance in the surgical unit and their age, while there was statistically significant relation between factors affecting nursing performance in the surgical units and their marital status and their experience, statistically significant relation between studied nurses' knowledge and studied nurses' practice, anda significant correlation between studied nurses' knowledge and a studied nurses' practice. Conclusion: It was concluded from this study that nurses' performance depends on education, training, experience and attending of courses. Recommendations: The study recommended the importance of implementing an educational training program to improve nurses' performance regarding management of patient after surgery, and recommended to develop a good nurse job description.