Objectives To evaluate the therapeutic effects of molecular adsorbents recirculating system(MARS) on chronic severe hepatitis patients complicated with multi-organ failure. Methods Eighty-two patients of chronic severe hepatitis co mplicated with multi-organ failure were studied and they were randanly divided i nto two groups, 40 as MARS therapy group and 42 as control group. One hurdred an d ten sessions of MARS treatments were performed in MARS therapy group. Liver fu ndtion, hemogram ammonia level, blood coagulation analysis, blood urea nitrogen (BUN) and creatinine level before and after treatment were evaluatied. Results MARS therapy improved the result of aprognosis in dex MELD remarkably, presented in significant therapeutic effect on hepaticence phalopathy or brain edema, renal dysfunction, obstinate ascites as well as reversal development of SIRS, improved hemodynamic and respiratory function by selective e limination of accumulated metabolic toxins and adjusted electrolyte, fluid and acid base balance. Conclusions MARS can be applied safely as preferable liver support therapy for liver failure patients complicatied with multi-organ failure.