Objective: To evaluate the epidemiological, clinical, and radiological data of patients treated with XLIF, including the impact on quality of life, pain parameters, and improvement of lumbar lordosis. Methods: Retrospective longitudinal study, in which medical records of patients who underwent XLIF between 2017 and 2020 at Hospital do Trabalhador/UFPR were reviewed. Demographic characteristics and radiological aspects, such as the Cobb angle, were recorded. Clinical characteristics using parameters such as pain by VAS and the disability index by ODI were evaluated before surgery and 12 months after. Results: Female patients predominated (66.7%), with a mean age of 59.1 years (35-82 years). The length of stay, in the median, was three days, and the time to return to daily activities was three months. Only four patients (8.9%) had complications. The questionnaire analysis showed a significant difference between all scales’ pre and postoperative scores. The ODI showed an average reduction of 39.2%, and the median score of VAS in the postoperative period was half the preoperative period (reduction of 50%; p <0.001). The lordosis angle increased by 26.3% in the postoperative period (p <0.001). Conclusion: XLIF presents low complication rates, improves lumbar lordosis, and allows recovery from daily activities in a short period, in addition to performing a statistically significant improvement in quality of life and pain according to the VAS and ODI scales, being, therefore, a viable and effective treatment technique. Level of Evidence II; Retrospective Study.