In patients with chronic heart failure (CHF), persistent neuro-humoral activation of sympatho-adrenal system and hyperglycaemia facilitate the activation of pro-cytokine inflammation component, as one of the pathophysiological mechanisms of endothelial dysfunction (ED). Aim. To study nebivolol effects on clinical and functional status, left ventricular (LV) myocardial remodelling, inflammation markers, and ED in CHF patients with or without Type 2 diabetes mellitus (DM-2). Material and methods. The study included 65 patients with functional class (FC) I-III CHF (NYHA classification) of ischemic origin and LV ejection fraction (EF) < 50%. Mean age was 61,2 +/- 7,4 years; 35 participants were diagnosed with DM-2. Results. Additional beneficial effects of nebivolol, such as endogenous NO synthesis modulation and immune inflammation reduction, could explain its clinical effectiveness and prognosis improvement in patients with CHF and DM-2, as well as in CHF patients with normal carbohydrate metabolism. Conclusion. Hyperglycaemia has an important negative effect on anti-inflammatory defence mechanisms, CHF clinical course, and prognosis, which was demonstrated by high baseline levels of all clinical and hemodynamic parameters, inflammation markers, and ED in patients with CHF and DM-2.