AIM: To adapt cross-culturally the Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) for use in Greek patients with atrial fibrillation (AF) and to evaluate its psychometric properties.METHODS: Professional translators were involved in the inverse translation procedure. Twenty patients with AF participated in the cultural adaptation procedure. One hundred two consecutive patients participated in the validation process that included reliability (internal consistency, test-retest reliability) and validity assessment (face validity, construct validity).RESULTS: Greek AFEQT showed high internal consistency (Cronbach's alpha for overall scale: 0.97, subscales: Symptoms: 0.90, Daily Activities: 0.93, Treatment Concern: 0.91, Treatment Satisfaction: 0.83) and test-retest reliability (Spearman's rho: 0.99, p <0.001, Wilcoxon's test, p =0.959). Face validity was rated with a median of 7 by the patients. Finally, Greek AFEQT showed appropriate construct validity of demonstrating adequate convergent validity with the moderate to strong correlations of AFEQT domains with the Physical and Mental Component Summaries of SF-12 (Spearman's rho: 0.53-0.78, p <0.001).CONCLUSIONS: The Greek version of AFEQT has shown good psychometric properties and can be a useful tool in future studies on the quality of life of patients with AF. Hippokratia 2016, 20(4): 264-267.