Prevalence of obesity and type 2 diabetes has been increasing worldwide. Numerous epidemiologic studies have shown that overweight, obesity and weight gain are major risk factors for type 2 diabetes. Of persons with type 2 diabetes, 80 % to 90 % are overweight and obese (abdominal obesity as clinical feature of metabolic syndrome). Prevention and management of overweight and obesity in type 2 diabetic patients (obesity and type 2 diabetes are chronic life-long diseases) needs long-term aggressive non-pharmacological and pharmacological treatment. Results of many clinical studies, but especially clinical practice showed, that overweight or obese persons with diabetes lose less weight than do nondiabetic persons and may regain weight more rapidly (with same non-pharmacological and pharmacological treatment). Overall, the current data indicate that in management of obese diabetic patients (diabesity) come into advisement three levels of preventive and therapeutic approaches (combination of lifestyle changes (diet and exercise) with behavioral therapy, safety therapy with anti-obesity agents and using of antidiabetic agents that are neutral on body weight or promote weight loss.