Hydatid disease is uncommon in Humans. It rarely affects the bones and joints (0.5-4%). Frequent sites of bony involvement are vertebrae, pelvic bones, upper end of long bones e.g. humerus, femur and tibia.We report a case of 41-year old female with primary Hydatid cyst of the entire right femur. Patient complaint of severe pain and was non ambulatory since the last 2 months.Here, single staged Total Right Femur Replacement was done under General Anaesthesia. Patient was discharged after 6 days of hospital stay in a stable condition where physical rehabilitation was initiated after day one of the surgery, progressing to aided walking, standing and active lower limb exercises.Involvement of the entire femur was a challenging case. There is no consensus/gold standard treatment of severe cases. Given the involvement of the entire Right Femur along with spillage in the neighbouring muscles, patient underwent Total Femur Replacement with Hip and Knee Replacement.