Objective: This study assessed the outcomes of transforaminal lumbar interbody fusion (TLIF) in patients with degenerative spine conditions above the age of 65 years and investigate the effects of fusion levels on the sagittal balance parameters. Materials and Methods: This retrospective study reviewed patients with degenerative spine diseases who underwent lumbar fusion with the TLIF procedure older than 65 years. Patients with three or less segments involved in the fusion were assigned to the short-level fusion group, and the patients with more than three segments involved in the fusion were assigned to the long-level fusion group. The anteroposterior and lateral spine radiographs of the patients were used to measure pelvic incidence (PI), pelvic tilt (PT), sacral slop (SS), lumbar lordosis (LL), distal lumbar lordosis, thoracolumbar kyphosis, thoracic kyphosis (TK), T1 spinopelvic inclination (T1SPI), T9 spinopelvic inclination (T9SPI) and T1 pelvic angle (TPA). Results: The study included 45 patients, 28 females and 17 males, who met the inclusion criteria. The long- and short-level fusion groups comprised 25 and 20 patients, with the mean ages of 68.87 and 67.72 years and mean follow-up periods of 26.96±15.53 and 27.61±11.83 months, respectively. TK and T9SPI values showed no difference between the groups before and after surgery, but a statistically significant increase in the values was observed postoperatively in the patients who underwent long-level fusion. The preoperative SVA values were significantly higher in the long-level fusion group than in the short-level fusion group. No difference in the postoperative SVA values was found between the groups. The PT, PI, SS, TPA, T1SPI was not statistically differ between the groups before and after surgery. Conclusion: TLIF contributes to the improvement of the sagittal balance parameters in both short- and long-level fusions in patients above the age of 65 years with degenerative spine conditions.