In this case report, two cases of bilateral atypical femoral fractures after prolonged bisphosphonate therapy are described. Two elderly females had more than ten years of antiresorptive treatment with bisphosphonate, and they were diagnosed with bilateral atypical femoral fracture (AFF) after a dual energy X-ray absorptiometry scanning of the entire femoral shaft. They were both subjected to intramedullary nails and anabolic treatment. Currently, bisphosphonate treatment of osteoporosis has been reduced because of side effects such as AFF.