Background: Slipped capital femoral epiphysis, is a common condition of the proximal femoral physis that leads to slippage of the epiphysis relative to the metaphysis. Diagnosis can be confirmed with radiographs of the hip. Treatment is usually percutaneous screw fixation. Objective: To study the outcome and complications of closed reduction and internal fixation by percutaneous screw fixation in unstable slipped capital femoral epiphysis. Patient and methods: Our case report is 11 years old obese male patient with history of progressive right hip pain for 10 days prior to presentation to the hospital. BMI was 36.1 kg/m². Patient presented with right hip pain and inability to bear weight, radiological evaluation confirmed right hip unstable slipped capital femoral epiphysis that required emergency in situ fixation Result: close follow up of the patient to 6 months, patient regain full functional activity, he achieved a complete range of motion of the right hip with good outcomes and with no complications. The goal in such injuries is to achieve a stable hip joint with gradual rehabilitation to reach a good functional outcome Conclusion: Slipped capital femoral epiphysis occurs in adolescent age group, more affecting male and obese patient, and they are idiopathic in the majority of cases. The goal of treatment in such patients is to achieve a stable hip joint with gradual rehabilitation to reach the optimal functional outcomes