Introduction: Tibia is the most commonly fractured long bone in the body. Among the total tibial fractures, about 5-11% of fractures occur in the proximal one third of the tibia. Fractures of the proximal third of the tibial shaft, by virtue of being high-energy injuries, are less amenable to plating primarily because of soft-tissue problems, and plates delay weight bearing. External fixators can lead to pin-track infections and there are technical difficulties in preserving knee motion in these juxta-articular fractures. Hence, Interlocking nail remains as an option with benefits of load sharing, sparing the extraosseous blood supply, lesser chances of infections and avoidance of additional soft-tissue dissection, thereby minimizing the risk of postoperative complications. Also allows early joint mobilization and weight bearing with short hospital stay. Aim: To study the clinico-radiological and functional outcome of the patients with proximal one third tibial shaft fractures managed with interlocking nail. Materials and Methods: This Prospective Study consisted of 20 adult patients of either sex with proximal one third tibial shaft fracture managed by Interlocking Nail. Functional outcome was measured by the Johner and Wruh’s Criteria. Twenty patients were followed for minimum 6 month with fracture healing time was 12-18weeks. Results: After the end of 6 months follow up most of the patients showed excellent results (12patients, 60%), 5 patients (25%) falls under good category, 3 patients (15%) showed fair results and none of patient showed poor results.The observations and results of present study were compared to other studies. Conclusion: Meticulous intramedullary nailing of fractures of the proximal third of the tibial shaft, using all current surgical principles and techniques, has excellent clinico-radiological outcome and is relatively safe. We recommend a nail similar to a Sirus nail, but with a more proximal bend of the nail and no dynamic interlocking screw hole.