OBJECTIVE： To evaluate therapeutic efficacy of tolvaptan combined with levosimendan in the treatment of severe congestive heart failure （CHF）. METHODS： 100 severe CHF patients were randomly divided into basic treatment group， tolvaptan group， levosimendan group and drug combination group， with 25 cases in each group. All groups were given Digitalis， ACEI， spirolactone， furosemidum and other comprehensive treatment； tolvaptan group was additionally given tolvaptan （15 mg/time， qd）； levosimendan group given levosimendan [0.1 μg/（kg·min）] for consecutive 24 h； drug combination given tolvaptan （15 mg/time， qd） and levosimendan [0.1 μg/（kg·min）] for consecutive 24 h. Blood pressure， heart rate， dyspnea， the improvement of systemic clinical symptoms and 24 h urine volume were observed in 4 groups before and 7 d after treatment. The venous blood samples were collected to determine the change of Na+， K+， renal function， BNP and other related indicators； the changes of LVEDd， LVESd， LVEF， CI and other indicators were determined by UCG. RESULTS： 7 days after administration， compared with basic treatment group， the blood pressure， heart rate， BNP， LVEDd and LVESd of tolvaptan group， levosimendan group and drug combination group decreased significantly， while dyspnea， systemic clinical symptoms and LVEF were improved significantly， and 24 h urine volume and CI increased significantly， with statistical significance （P＜0.05）. The change of drug combination group was more significant， there was statistical significance， compared with tolvaptan group and levosimendan group （P＜0.05）. There was no significant difference in serum electrolytes and renal function. CONCLUSIONS： Tolvaptan combined with levosimendan is effective and better than drug alone in the treatment of severe CHF.