Total parenteral nutrition for hospitalized critically ill patients is essential for improving outcomes, insufficientnutritional support lead to occurrences of complications, increased morbidity and mortality rates, increased lengthof hospital stay. Critical care nurses are the cornerstone in preventing theses complications. Aim: To investigatethe effect of implementing total parenteral nutrition nursing guidelines on adult critically ill patients’ outcomes.Design: Non randomized prospective research design was used to utilize this study Subjects: convenience samplesof 60 patients were assigned equally to study and control group at intensive care units at Assiut University hospitals.The control group received routine hospital care during TPN administration while, the study group received thedeveloped guidelines for TPN during a period from January 2018 to December 2018. Methods Each patient inboth groups were assessed by taking history, clinical examination, nutritional assessment laboratory investigation.Patients in study groups were received care according to developed total parenteral nutrition guidelines todetermine outcome and complications in both groups. Results Finding of the present study revealed that significantimprovement in study group with values of less than p=001 compared to control group Conclusion: implementingof total parenteral nutrition guidelines improve the outcomes and reduce the occurrence of complications amongcritically ill patients.