Background: All stakeholders in the healthcare system have prioritized and will continue to prioritize enhancing care quality. The measurement of sinus-specific quality of life (QOL) is potentially the most commonly used QOL parameter for chronic rhinosinusitis (CRS). Objective: A systematic review and meta-analysis were used in this study to determine the mean change in patients’ scores on the 22-item Sino-Nasal Outcome Test (SNOT-22) before and after endoscopic sinus surgery (ESS) for CRS. Methods: PubMed, Google Scholar, and ScienceDirect were searched for articles that compared SNOT-22 scores before and after ESS in adult patients with CRS and were published between January 2000 and March 2023. The mean post-op change, 95% confidence interval (CI), forest plot, and inverse variance weighting were all generated using a random effects model. A mixed-effects meta-regression was used to analyze the effect of patient-specific characteristics across studies. Results: Fifteen prospective patient cohorts published from 2009 to 2023 were included in this meta-analysis. At an average follow-up of 25.5 months, all studies demonstrated a statistically significant difference in mean SNOT-22 scores between baseline and post-op time periods ( P < .05), ranging from 5.1 to 55.4. Across all studies, the mean SNOT-22 changed significantly by 26.02 (95% CI: 12.83-38.60). According to a stepwise multivariate analysis, studies with higher mean age and mean pre-op SNOT-22 scores had greater changes in SNOT-22 scores following ESS, whereas trials with longer mean follow-up duration had smaller changes in SNOT-22 scores. Conclusion: Research utilizing the SNOT-22 instrument has demonstrated that endoscopic sinus surgery (ESS) leads to enhanced quality of life (QOL) outcomes. The literature reports that improvement is influenced by the initial SNOT-22 score, the mean age of the patients, and the duration of the follow-up period.