Avulsion fractures of the calcaneal tuberosity are predominantly seen in patients with poor bone quality, the commonly used lag screw fixation might not be strong enough even with bony fragments of sufficient size. We present a case of a closed displaced avulsion fracture of the calcaneal tuberosity due to blunt trauma to the calf in a 74-year-old female. Open reduction and internal fixation with two 3.5-mm cannulated cortical screws with washers was performed, and anatomic reduction was achieved. Without further trauma, secondary displacement of the fracture occurred on day 3. Revision was performed with a single 3.5-mm cortical screw and transosseous fixation with 2 suture anchors, followed by partial weightbearing for 6 weeks. At 12 weeks postoperative, the fracture had completely healed, and she was doing well at 16 months after the revision surgery. Transosseous suture anchor fixation of an osteoporotic avulsion fracture of the calcaneal tuberosity seems to provide better and stronger fixation than that using lag screws.