This research aims to study the relationship between mandibular alveolar resorption and the effect of complete dentures on oral health-related quality of life. Study materials and methods: The research sample included 100 patients treated with conventional complete dentures at the Department of Removable Prosthodontics at Damascus University. Patients’ selection was based on general health and previous denture use. In order to avoid effects of health problems on oral health-related quality of life, healthy edentulous patients were selected. And who had not previously used any dentures; to avoid the impact of previous experiences. Oral health-related quality of life (OHRQoL) was measured twice using the Oral Health Impact Profile (OHIP-EDENT). The first measurement was during the first session, and the second one was one month following the treatment with complete dentures and after making all the adjustments. The results were collected and analysed through the statistical program SPSS version (24). Statistical tests: T-Test for paired samples, One Way ANOVA TEST were used and the significance level was set at P<0.05. Results: The results showed that after treatment with complete denture all domains of the OHIP-EDENT showed significant improvements (p-value=0.001). There was no significant differences between alveolar bone resorption and (OHRQOL). Conclusion: Conventional complete dentures improve oral health-related quality of life.