Objectives: Periodontal disease is a chronic, infectious gum disease, which eventually leads to tooth loss, adversely affecting quality of life (QoL). Most of the research in this area focuses on evaluating clinical parameters rather than patient-based outcomes. Currently, these parameters are gaining importance along with treatment outcomes of chronic diseases and QoL. This study evaluates the impact of periodontal disease and its treatment on oral health-related quality of life (OHRQoL)., Methods: We recruited 90 participants who were divided into two groups. One was the test group (n = 45) that underwent non-surgical periodontal therapy (NSPT) followed by periodontal flap surgery (SurgPT). Second was the control group (n = 45) that underwent only NSPT. Clinical parameters, plaque index, gingival index, periodontal/probing pocket depth (PPD), clinical attachment level (CAL), and mobility were recorded. An OHRQoL questionnaire was used to assess the functional, physical, social, and psychological domains at baseline, three, and six months., Results: The mean PPD in the test group was 6.9 ± 0.38, 3.2 ± 0.36, 3.5 ± 0.5, and 5.8 ± 0.67, 3.13 ± 0.21, 3.73 ± 0.45 in the NSPT group at baseline, 3, and 6 months, respectively. The mean CAL in the SurgPT group was 7.07 ± 0.41, 3.56 ± 0.27, 3.74 ± 0.30, and 6.08 ± 0.16, 4.02 ± 0.17, 4.16 ± 0.19 in the NSPT group at baseline, 3, and 6 months, respectively. Both treatments resulted in reduction in all clinical parameters and were statistically significant in the SurgPT group ( p < 0.001). Oral Health Impact Profile scores substantially decreased in the SurgPT group (mean difference-25.0) compared to the NSPT group (mean difference-5.0) ( p -0.001)., Conclusions: In this study, NSPT and SurgPT had a positive impact on OHRQoL by improving clinical parameters, but SurgPT had substantially better outcomes in terms of improved QoL., (© 2021 Taibah University. Production and hosting by Elsevier Ltd.)