Introduction: Atrial fibrillation (AF) and frailty syndrome (FS) are a part of the aging process. Both are still of great importance in the assessment of quality of life (QoL). There is definitely a lack of research clarifying the association between FS and QoL in AF patients. Objective: The aim of this study was to evaluate the influence of FS on QoL in AF patients. Materials and Methods: The retrospective and observational study included 158 inpatients with mean age 69.8±7.1 years, treated for AF in the cardiac department from 1 April 2019 to 31 June 2019. The following instruments were used: the Arrhythmia-Specific Questionnaire in Tachycardia and Arrhythmia (ASTA) and the Edmonton Frail Scale (EFS). Results: The mean level of frailty in the study group was 8.5±5.0. In 25.9% of patients, the level of frailty was mild, in 10.1% moderate, and in 17.1% severe. Patients were divided into two groups based on their frailty status. In comparative analysis of the QoL, there were significant differences between the groups: the frail group had more intense symptoms of arrhythmia than the non-frail group (14.9±4.1 vs 11.9±4.9; p<0.001). In the analysis of the total score impact of arrhythmia on QoL, the frail group had a significantly higher score than the non-frail group (23.5±5.2 vs 14.5±5.5), which confirmed the stronger negative impact of arrhythmia on QoL. In the regression coefficient analysis, the independent predictor of symptom severity and QoL was FS. However, we observed a negative impact of diabetes, which increased the impact of arrhythmia on QoL, and physical activity, which improved QoL and decreased the impact of symptoms on everyday life. Conclusion: Patients in the frail group have worse QoL and higher impact of arrhythmia on QoL in comparison to patients in the non-frail group. Frailty is an independent predictor of higher intensity of symptoms of arrhythmia and worse QoL. Diabetes and physical activity are predictors of QoL for patients with AF.