Background. Rotator cuff tear is a common condition that affects majority of people at some point during lifetime. The purpose of this study was to investigate if smoking minimum 1 pack year before arthroscopic rotator cuff repair is an additional risk factor for lesser outcomes among patients suffering simultaneously of diabetes type 2. Material and methods. 40 patients Aged 41-74 operated on between 2017-2020 at St. Lukes Hospital by the same team, were dived into 2 groups. 26 of them suffered Diabetes Mellitus t. 2 prior to surgery and 14 apart from DM t.2 declared additionaly current smoking for at least 1 pack year before the repair. The patients were then assessed pre-op and at 3 and 6 months post-op using QuickDASH score and VR-12 questionnaire. The patients were also investigated for early complications rate within 90 days post-op as well as for secondary hospitalization within 30 days post- op. Results. Using standard statistical procedures, the study revealed significantly worse repair outcomes in the smokers group confirming the hypothesis. None of the patients regardless of smoking status and comorbidities suffered any complication or secondary hospitalization during first 3 months post-op .Conclusion. Smoking at least 1 pack year prior to arthroscopic rotator cuff repair is an additional factor for lesser outcomes.