Background: Femoral neck fractures are common in the geriatric population and are associated with high morbidity and mortality. The worldwide incidence of hip fractures is expected to approach 6.26 million by 2050. Studies showed that the functional outcome and pain scoring were improved in cases of femoral neck fracture treated by total hip arthroplasty than any other methods. Objective: Assessment of functional and radiological outcomes of treatment of femoral neck fractures by total hip arthroplasty. Materials and Methods: This study was performed on 18 patients presented with history of fracture neck femur who were admitted to Orthopedic Department, Zagazig University Hospital in the period from January 2019 to December 2019. All cases in this prospective study were treated by total hip arthroplasty (THA). All the patients were operated through Harding's approach. Both cemented and un-cemented types of arthroplasty were performed. Functional outcomes of hip were evaluated at 3 months and 6 months after surgery. Results: 66.7 % of studied group had history of previous fixation. Previous operative fixation for neck femur (NF) fracture were 50 % cannulated screw, 25 % DHS and 25% IMN. Regarding cause of lesion most frequent were failure of other fixation for NF (66.7%) then acute NF associated with OA (22.2%) and neglected N F fracture (11.1%). Conclusion: Total hip arthroplasty is one of the most successful orthopedic surgical procedures and has regained popularity during the last few decades with minimal pain.