Purpose : To evaluate the role of CT in early detection, location, and extent of osteochondritisdissecans(OCD) of the elbow joint. Materials and Methods : We reviewed surgically proved 27 cases of 22 patientswith osteochondritis dissecans in elbow joint retrospectively. We compared simple x-ray(elbow AP & lateral) withCT on the basis of staging of OCD of talus by simple x-ray. Results : The frequency of location was asfollows:fourteen cases of capitellum, 5 cases of olecranon tip, 5 cases of medial epicondyle, 2 cases of trochlea,and 1 case of olecranon base. Among the 4 cases of normal finding on simple x-ray, CT showed 1 case of stage I,II, III, and IV OCD and among the 8 cases of stage I on simple x-ray, CT showed 2 cases of stage I, 1 case ofstage II, and 5 cases of stage III. Among the 3 cases of stage II on simple x-ray, CT showed 1 case of stage IIand 2 cases of stage III, Among the 5 cases of stage III on simple x-ray, CT showed 1 case of stage II, 2 cases ofstage III, and 2 cases of stage IV, but it was difficult to detect the presence or absence of attachment betweenthe articular cartilage of mother bone and osteochondral fragment. CT was more accurate than simple x-ray indetection of loose body. Conclusion : CT might be an useful imaging modality in early diagnosis of OCD andevaluation of its anatomic location and extent in elbow joint.