A 11 month-old Shihtzu was referred to the Veterinary Medical Teaching Hospital, Seoul National University. Clinical signs of this patient were lameness, shortening limb, angular deformity, rotation of foot, subluxaion of elbow joint and restricted range of movement of left forelimb. For the evaluation of the abnormalities of left forelimb, radiographic examination was carried out. Radiographic findings were characteristics of premature closure of distal ulna such as closure of distal ulna growth plate and cranial bowing of radius. With radiographic signs and physical examination, it was diagnosed as premature closure of growth plate of the left forelimb. After osteotomy of the radius and ostectomy of the ulna, radiographic evaluation of limb about angulation of elbow joint was performed every 2-3 weeks for 3 months. In case of premature closure of distal growth plate of ulna, radiography was very useful for diagnositic method of premature closure of distal ulna and monitoring of healing process.