A four-year-old Standardbred gelding was examined because of vague right hind limb lameness of 3 to 4 months' duration. Results of physical examination, radiography, and scintigraphy were indicative of a chronic comminuted fracture of the proximal portion of the right fibula. A cancellous bone graft was placed in the fracture site, and 3 months later, the fracture appeared to be healed radiographically. Fractures of the fibula are rare in horses and should not be confused with normal anatomic discontinuities that result in a bi- or tripartite appearance of the fibula on radiographs. Because the fibula is a non-weight-bearing bone in horses, lameness associated with fibular fractures may be vague.