Morbid obesity adversely affects quality of life. The assessment of health-related quality of life (HRQoL) needs specific measuring instruments. The Moorehead-Ardelt Quality-of-Life Questionnaire II (MA II) is an obesity-specific instrument widely used in bariatric surgery. The objective of this study was to translate and validate the MA II in Greek language. The study included the translation of the MA II followed by cross-validation with the Greek version of 36-item Short Form Health Survey (SF-36) and a Visual Analogue Scale (VAS) in subjects visiting an obesity clinic. Internal consistency was indicated by Cronbach's alpha coefficient and test-retest reliability by intraclass correlation coefficient (ICC). Construct validity was studied using Pearson's correlations between the MA II, the SF-36 and the VAS. A total of 175 patients were enrolled in the study. Test-retest analysis was applied to 40 patients with a 15-day interval. A very good internal consistency with Cronbach's alpha coefficient of 0.85 was shown. Excellent test-retest reliability was observed with an overall ICC of 0.981. Significant correlations between the Greek MA II and the other instruments as well as of each item of the MA II with the scores of SF-36 and the VAS indicated high construct and convergent validity. A negative correlation between the translated MA II total score and BMI confirmed high clinical validity. The Greek version of the MA II questionnaire has been generated and shown to be valid and reliable in measuring HRQoL in morbidly obese patients before and after bariatric surgery.