Background: Distal femur fracture accounts 6 % of all femur fractures. Treatment of distal femur fracture is one of the orthopedic challenges. Historically nonoperative management was the mainstay of management which now evolved to operative management. There is no single implant used for all type of distal femur fractures. Implants are evolving with time parallel with advancement of technology. Objective: To assess functional outcome of open reduction and internal fixation of distal femur fracture by distal femur locking plate and its associated factors at Tibebe Ghion Specialized Hospital, Bahirdar, Ethiopia. Material and Method: This prospective cohort study was carried out among adult patients with distal femur fracture treated by open reduction and internal fixation using distal femur locking plate at Tibebe Ghion Specialized Hospital from august 2022 to July 2023. Using convenient sampling technique, a total of 60 patients with both AO Type A and Type C fracture were included. All patients were followed at 2 wks., 6wks ,12 wks. and 6 months. Functional outcome was assessed using Neer’s scoring system. Data was entered and analyzed using SPSS 27. Frequency, mean and cross tabulation were used to summarize descriptive statistics. Multinomial logistic regression was used to test the association of independent variables with functional outcomes. Result: In this study out of 60 patients, 48.3% patients had excellent, 30% had good, 10% had fair and 11.7% of patients had poor functional outcome by Neer’s score system. On the last follow up, 23.6 % of patient had stiffness, 16.7% had pain and 8.3 % had infection. Compared to patient with open fracture patient with closed distal femur fracture had 49 % higher chance of having excellent functional outcome (AOR (2.49(5.8 ,1.07)). Patient who had regular follow up had 7 times higher probability of excellent functional outcome than those who had no regular follow up (AOR 7.16(1.11,46.22)). Conclusion and recommendation: This study found higher functional outcome among patients with AO Type A and Type C distal femur fracture treated by open reduction and internal fixation using distal femur locking plate. Closed fractures and having regular follow up were factors associated with excellent functional outcome. Public awareness about gun handling and peaceful conflict solving culture by government should be advocated. All patient should have regular follow up. Key words: distal femur fracture, Neer’s score, distal femur