This paper reports the posterior lumbar interbody fusion (PLIF) that has been performed on fourteen patients. It includes 6 cases of spondylolytic spondylolisthesis, 3 cases of degenerative spondylolisthesis, 2 cases of postoperative recurrence of lumbar disc protrusion, 2 cases of unstable prolapse of intervertebral disc, 1 cases of consequent spinal canal stenosis after lumbar lamina fusion. As a result 92 per cent of the operations are successful. The method of operation and it's modification are reported in detail. The indication of operation and the evaluative criteria of interbody bone union discussed. The intact of lumbar posterior structures, the condition of bone grating bed, the quality and disperse of bone graft are main factors that influencing bone union. Bleeding from venous plexus of spinal canal and from vertebral cancellous bone, injury of lumbosacral nerve root and cauda equina are the main surgical complications that should be stressed.