A total of 29 patients diagnosed degenerative lumbar spine stenosis or spondylolisthesis underwent decompression and one- or two-segment posterolateral spine fusion with pedicle screws fixation at the Department of Orthopaedics, Beijing Hospital of Ministry of Public Health from January to December 2005. Equal quantities of autogenous laminectomy bone supplemented with calcium sulfate were placed in both posterolateral gutters. 29 patients were followed-up ranged from 2.5 to 3.5 years, averaging 3.1 years. Calcium sulfate was completely absorbed 6 months following surgery. For the 12 patients who received single-segment fusion, 7 patients exhibited bone fusion on both sides and 3 patients were diagnosed having doubtful fusion, as well as 2 patients were not fused. For the 17 patients who received two-segment fusion, 8 patients exhibited bone fusion on both sides and 4 patients were diagnosed doubtful fusion, and 5 patients were not fused. Score of Oswestry Disability Index (ODI) was (82.40±4.82) points prior to surgery, but (9.20±1.56) points 3 years following surgery, resulting in an improvement rate of 88.3%. This indicated that as a bone graft extender in short-segment spinal fusion, the absorption of calcium sulfate pellets was comparatively faster, and completely degraded in half a year, with a high total fusion rate.