Background: Enteral feeding intolerance may affect the effectiveness of enteral feeding, thereby prolonging hospital stay, influencing mechanical ventilation and increasing mortality rate. Aim: is to investigate the frequency, risk factors, and clinical manifestations for tube feeding intolerance among critically ill patients. Research design: A descriptive exploratory survey research design was utilized to conduct this study. Subjects: A purposive sample of sixty-five adult male and female critical ill patients that they are receiving enteral feeding in first 24-48 hours of admission. Setting: This study was conducted at intensive care units at Assiut University Hospital, Egypt. Tools: Tool I: Adult critically ill tube feeding intolerance clinical manifestations assessment questionnaire. Tool II: Nutrition status assessment tool by using The Mini Nutritional Assessment Short-Form. Tool III: Risk factors of enteral feeding intolerance assessment questionnaire. Results: The majority of patients (84.6%) manifested by equal to or more than two symptoms of enteral feeding intolerance, the mean age of patients was (36.57±10.34) and (55.4%) were males. Conclusion: Based on the results of this study, many patients suffered from vomiting, constipation, flatulence, abdominal distention or straining. There were several risk factors for enteral feeding intolerance as constipation, stress and bed rest. Recommendations: Further research studies and in-service education for critical care nurses regarding to proper nutrition, assessment of enteral feeding intolerance among critically ill patient from time of admission.