Background: Posterior lumbar interbody fusion (PLIF) is a fusion technique with reliable and rapid fusion results. This prospective, controlled, randomized clinical study critically compared the clinical and radiological outcomes in patients surgically treated by PLIF with bone graft alone versus those treated by PLIF with cage with bone graft. Objectives: The purpose of the current study is to asses the safety and efficacy of lumbar interbody fusion.Also,direct comparison of both materials in terms of clinical and radiological outcomes. Patients & Methods: In the period between November, 2018 and July, 2019, 24 cases of degenerative lumbar spine disorder selected according to the inclusion and exclusion criteria for posterior lumbar interbody fusion. Results: The follow-up period was 9 months. Pain and functional VAS scores showed marked improvement. from 7.1to 2.25 in group I (bone graft alone), while Group II (cage with bone) decreased from 7.5 to 2. The mean Oswestry Disability Index decreased from 45 to 18 in group I, while group II decreased from 51 to 22. The fusion rate was 83.3% in the first group and 91.7% in the second group. There was no statistically significant between both groups. In both groups, changes in disc height, and whole lumbar lordosis between the pre-and postoperative periods were significant in both groups.Conclusions: Both techniques after PLIF produced satisfying clinical and radiological outcomes such as maintaining the proper intervertebral disc space restore lumbar lordosis, good boney union, rigid stability and a high fusion rate. but no statistical difference between both groups.