Triceps tendon avulsion from the olecranon is a rare injury. Missed or delayed diagnosis may result in a weakness of strength or a decreased range of motion of the elbow. This injury is usually caused by a fall on the outstretched hand or a direct blow to the posterior arm. In addition, the rupture of the triceps tendon is implicated by a sudden eccentric contraction of the triceps muscle. To determine whether the rupture is complete or incomplete is critical to guide the treatment method. A small avulsed fragment from the olecranon may be detected on lateral radiographs of the elbow. We report three cases of the triceps tendon avulsion with a bony flake from the olecranon, which were surgically treated, along with a brief review of the literature.