Background/Aim: Lumbar spinal stenosis (LSS) is a disease that affects the quality of life of elderly individuals. Most patients undergoing surgery for lumbar spinal stenosis try physical therapy before opting to undergo surgery. The effect of pre-surgical exercise treatment is unclear. This study aimed to examine the effect of pre-surgical exercise treatment on functionality, quality of life, and balance. Methods: Patients between the ages of 40 and 70 who were scheduled for surgery based on a diagnosis of LSS were included in this cross-sectional study. The patients were randomly divided into two groups for which exercise therapy was added to the first group before the surgery, and the control group followed in the normal process. Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), Beck Depression and Anxiety Inventory (BDI and BAI, respectively), Berg Balance Scale (BBS), static and dynamic balance measurements holding hands on and off on the balance device (SBHON, DBHON, DBHOFF) and the SF-36 quality of life scale tests were administered pre-operatively and eight weeks post-operatively, and the results were compared between the two groups that did and did not exercise before surgery. Results: Post-operative SBHON values were found to be significantly lower in the exercise group compared to the other group (P < 0.001). While no differences between pre- and post-operative BBS, DBHON, and DBHOFF values in the non-exercising group were detected, a favorable significant difference in the exercising group was found (all P < 0.001). Conclusion: The addition of pre-surgical exercise therapy to patients can lead to improvements in the success of surgery and contribute to the functionality of patients with LSS diagnosis.