The lumbosacral fusion has some problems because of it's biomechanical characteristics especially in the unstable spine of various causes and results considerable cases of pseudoarthrosis even with long immobilization. The conventional internal fixators for the spine are not adequate for the lumbosacral fixation with difficulty of sacral fixation maintaining lumbosacral lordosis and risk of the sacral nerves. Recently the pedicle screws and sacral screws connected to the plates or rods are known to be very effective and safe for the lumbosacral fixation permiting early mobilization and decreasing the incidence of pseudoarthrosis. Authors reviewed 10 cases of lumbosacral fusion with internal fixation using the long bone plates and screws which were managed since June 1986 at the department of orthopaedic surgery, Daegu Fatima Hospital and the followings were obtained. 1. The cases were 5 isthmic and 5 degenerative spondylolisthesis with enough spinal stenosis and instability before surgery or after decompression procedures having ages from 39 to 62 years old. 2. All cases had adequate decompression and bilateral intertransverse fusion combined with the internal fixation from 4th lumbar spine to sacrum. 3. Post-operative complications noted in 3 cases such as superficial infection, marginal skin necrosis, paralytic ileus, urinary difficulty and loosening of screws which were all improved without additional procedures. 4. There was no pseudoarthrosis at follow-up examination of 6 months to 1 year and 9 months in spite of a case of loosening of screws. 5. Ambulation was allowed in 2 weeks after surgery wearing lumbosacral corset and all satisfied the results having complete or significant improvement of the symptoms. 6. The internal fixation using long bone plates and screws for the lumbosacral fusion was considered to be effective with very low cost and good mobility.