Background: This study investigates the quality of life (QoL) among individuals in Lebanon post-COVID-19 vaccination, focusing on various demographic and lifestyle factors influencing physical, psychological, social, and environmental health domains. Objective: To explore the associations between COVID-19 vaccination status and QoL across four sub-scales: physical health, psychological health, social relationships, and environmental quality, examining the impact of gender, tobacco and alcohol consumption, chronic diseases, physical activity, employment status, education level, geographic location, and marital status. Methods: A cross-sectional study was conducted involving 507 Lebanese adults who completed a structured questionnaire. The questionnaire collected data on demographics, lifestyle factors, and QoL using a standardized measurement tool. Statistical analysis, including bivariate analysis, was performed to determine significant associations between independent variables and QoL scores across the four domains. Results: The majority of participants were female (71.6%), non-smokers (83%), and non-drinkers (76.7%). Most had no chronic diseases (83%), and 42.4% engaged in regular physical activity. High educational attainment (80.5% with graduate or professional degrees) and full-time employment (77%) were prevalent. Significant associations were found between gender and all QoL domains, with males reporting higher scores. Physical health scores were higher among non-drinkers, the physically active, independent workers, and vaccinated individuals. Psychological health was better in males, the physically active, and independent workers. Social relationships were stronger among males, independent workers, and those in relationships. Environmental quality was higher among males, non-drinkers, independent workers, and those with no formal education. Vaccination status positively influenced physical health and showed near-significant effects on social relationships and environmental quality. Conclusion: COVID-19 vaccination is associated with improved QoL in Lebanon, particularly in physical health. The findings highlight the importance of considering socio-economic factors and lifestyle choices in public health strategies to enhance overall well-being. Future research should explore longitudinal impacts and address the specific needs of diverse populations.