Background: Degenerative lumbar spine disease is a clinical condition characterized by low back pain (LBP) associated with radiculopathy and other features of neurologic dysfunctions. The quest to achieve pain (LBP and leg pain) relief is usually one of the reasons patients present for decompressive surgery in the study population. Pain outcome studies are therefore essential following these surgical procedures to ascertain whether patients improve or not in the short-term or long-term using Objectives: The study assessed pain outcome of lumbar decompressive surgery for degenerative lumbar spine diseases using patient-reported pain outcome assessment tools. It also determines whether some factors (age, sex, body mass index and symptoms duration) influence pain outcome of patients following surgical intervention. Methodology: This is a prospective, longitudinal study that was carried out in Memfys Hospital for Neurosurgery. Consenting patients who were aged 40years and above and had lumbar decompressive surgery for symptomatic degenerative lumbar spine disease were assessed for radicular pain and LBP using the metric visual analogue scale (VAS) and Oswestry disability index (ODI). This assessment was carried out at the immediate preoperative period and six months following surgery. Data obtained were analyzed using descriptive and inferential statistics. The preoperative and postoperative VAS and ODI scores were compared. The effect of gender, age, body mass index (BMI) and duration of symptoms on the postoperative mean change in VAS and ODI were also assessed. Results: A total of 67 patients completed the study with 36(54%) male and 31(46%) female. The mean age of the study population was 55.28 years. The mean BMI was 29.60 kg/m2, and mean duration of low back and radicular pains were 38.39 and 23.58 months respectively. At six-month postoperatively, there was significant pain reduction from preoperative baseline VAS for low back pain (67.12 to 32.74), VAS for radicular pain (75.39 to 32.75), and ODI (65.30 to 27.66) with p <0.001. Radicular pain was more significantly reduced than LBP by lumbar decompression surgery (p = 0.03). Long duration of symptoms (lasting more than 12 months) was found to be a predictor of poor outcome using the ODI scale (p = 0.047). Also, females showed a more substantial improvement in ODI compared to males (p = 0.022). Patients’ age and BMI did not significantly affect outcome in any of the pain outcome variables (p > 0.05). appropriate Conclusions: Patients with symptomatic degenerative lumbar spine disease can expect a meaningful improvement as defined by this study, in pain intensity and pain-related functional disability at six-month after lumbar decompression surgery. Patients with longstanding pain symptoms prior to operation are less likely to improve six-month after surgery. Also, female patients experienced more postoperative pain reduction at six-month compared to male. At the same time, patients’ age and BMI did not significantly influence pain outcome. Keywords: Degenerative lumbar spine disease, Decompressive surgery, VAS, ODI, Pain outcome assessments t