Concomitant ipsilateral fractures of the humerus and forearm bone are rare and result in a so called floating elbow. The injury resulted from severe trauma, acompanied with many associated injuries. It is controversial in the treatment because of functional disability. Authors analysed 15 cases who had received operative treatment at Department of Orthopedic Surgery, College of Medicine, Chosun University from Jan. 1985 to Feb. 1990. 1. The most common cause of injury was a traffic accident. 2. We treated these fractures surgically in most cases, and obtained satisfactory result. 3. The average time of bone union in. the closed fracture group was 13.2 weeks in the humerus, 14.4 weeks in the radius and 14.8 weeks in the ulna and in the open fracture group 14.2 weeks in the humerus, 15 weeks in the radius and 16.2 weeks in the ulna. 4. The functional result was good in 8 cases, fair in 3 cases and poor in 4 cases according to Lange and' Foster method. 5. The complications were delayed union in 5 cases, partial ankylosis of elbow in 4 cases, nerve injury in 3 cases and nonunion in 1 case. 6. We think that accurate understanding to the fracture complexity before treatment can obtain good results.