Background: Pressure ulcers are common health problems that represent a nursing and social burden. Mortality risk in a patient with pressure ulcer is two to six times greater than this in a patient with intact skin. Aim of the study is to evaluate the effect of implementing evidence based practices guidelines on immobilized orthopedic Patients' Outcome regarding Pressure Ulcers. Method: Quasi-experimental research design was used to conduct this study in orthopedic unit at Benha University Hospital. A purposive sample of sixty adult patients was recruited in this study, divided equally into study and control groups. Two tools were used for data collection. Tool I; Comprehensive skin assessment sheet and tool II; Braden Risk Assessment Scale. Results: There was statistically significant difference between the study and control groups regarding Patients' Outcome regarding pressure ulcers post-implementation of evidence based practices guidelines. On the other hand, orthopedic immobilized patients who received routine nursing care developed several and higher stages of pressure ulcers.  Conclusion: Implementation of evidence based practices guidelines was highly effective in improving orthopedic immobilized patients' outcome regarding pressure ulcers as compared with orthopedic immobilized patients who received routine nursing care. Recommendations: Evidence based practices guidelines for prevention of pressure ulcers should effectively be implemented for orthopedic immobilized patients who are assessed as being at pressure ulcers risk.