Percutaneous endoscopic gastrostomy (PEG) is a method of enteral nutrition applied in the case of patients at risk of malnutrition and undernourished patients in specific clinical conditions. Aim of the study: was to assess nurses’ performance regarding care of post percutaneous endoscopic gastrostomy patients in critical care units. Design: A descriptive exploratory research design was used. Setting: The study was conducted in the endoscopy & critical care units at El-Fayoum General Hospital. Subjects: A Convenient sample of all available nurses (50) nurse from both sex working in endoscopy & critical care units. Tools: two tools were used for data collection. Tool I: Nurses’ self-administered interview Questionnaire: which included (a) Demographic characteristics of nurses (b) Nurses’ knowledge regarding care of post percutaneous endoscopic gastrostomy patients Tool II: Observational check list to assess nurses’ practice regarding care of post percutaneous endoscopic gastrostomy patients. Results: the study results reported that 64%, 78% of the studied nurses had unsatisfactory level of total knowledge and incompetent level of total practices regarding care of post percutaneous endoscopic gastrostomy patients respectively. Additionally, there was a statistically significant correlation between total knowledge and practice regarding care of post percutaneous endoscopic gastrostomy patients. Conclusion: The study concluded that nearly two thirds of the studied nurses had unsatisfactory knowledge, and more than three quarters of them had incompetent level of practice regarding care of post percutaneous endoscopic gastrostomy patients. Additionally, there was a statistically significant correlation between total nurses’ knowledge and practice regarding care of post percutaneous endoscopic gastrostomy patients. Recommendations: Continuing educational program to improve knowledge and practices of nurses regarding care of post percutaneous endoscopic gastrostomy patients.