Morbid obesity together with obesity-related diseaseshave a negative impact on the quality of life. The aim of thestudy was to assess the quality of life among patients withmorbid obesity as well as the impact of bariatric treatmenton body weight and obesity-related diseases in addition toconducting an analysis of changes in the quality of life aftersurgical treatments, in the context of the surgical proceduretype and degree of body weight loss.In the 2nd Surgical Department of the JagiellonianUniversity Medical College 148 patients were treated formorbid obesity. The sample group consisted of 31 patientstreated with laparoscopic sleeve gastrectomy and 34 personsqualified for gastric-intestinal bypass surgery. The averagebody weight before the procedure was 146.2 kg. In thesample group 89% of persons qualified for the surgicaltreatments were diagnosed with hypertension and 52%persons that were operated on were diagnosed with diabetestype 2 before the surgical procedure.Before commencement of the surgical treatment, thequality of life was assessed, which in both groups qualifiedfor given types of bariatric procedures was considerablylow.The percentage excessive weight loss (%EWL) was 58.8%.No significant differences in body weight loss were notedbetween the two types of procedures. Improvement wasobserved in treatment of obesity-related diseases. Also thequality of life was enhanced significantly. No differenceswere noted in terms of quality of life improvement betweenparticular types of surgical procedures. No significantdifferences were observed during the analysis of bodyweight loss impact on quality of life improvement.