Objective To observe the effect of plasma exchange( PE) therapy for removing serum interleukin- 6( IL- 6),tumor necrosis factor alpha( TNFα),and interferon gamma( IFNγ) in patients with liver failure,and to assess the value of artificial liver support system in the treatment of liver failure. Methods The study included 36 patients with liver failure who were hospitalized in the First Affiliated Hospital of Bengbu Medical College from February 2012 to February 2013. Blood samples were collected before PE and the next morning after multiple treatments. Plasma TNFα,IL- 6,and IFNγ levels were measured by ELISA. Between- group comparison of measurement data before and after treatment was made by independent- samples t test,and comparison of mean values between groups was made by analysis of variance. Results All the 36 liver failure patients had significantly lower levels of TNFα( 381. 23 ± 190. 57 ng / L vs 274. 12 ± 212. 30 ng / L,P< 0. 05),IL- 6( 77. 9 ± 83. 09 ng / L vs 54. 8 ± 63. 32 ng / L,P < 0. 05),and IFNγ( 534. 65 ± 471. 19 ng / L vs 259. 65 ± 312. 26 ng / L,P< 0. 05) after treatment than before treatment. According to the severity of clinical manifestations,the patients with subacute or acute- on- chronic( subacute) liver failure were divided into early stage,middle stage,and advanced stage groups. There were significant differences in IL- 6 and TNFα decreases between the early stage,middle stage,and advanced stage groups( P < 0. 05). IFNγ decrease significantly differed between the early stage or middle stage group and advanced stage group( P < 0. 05),but not between the former two groups( P > 0. 05). After PE therapy,29 out of 36 liver failure patients recovered well,while the remaining 7 patients deteriorated. The recovered group had significantly greater decreases in TNFα( 122. 58 ± 57. 64 ng / L vs 42. 45 ± 19. 86 ng / L,P < 0. 05),IL- 6( 26. 93 ± 7. 25 ng / L vs 6. 71 ± 3. 55 ng / L,P < 0. 05),and IFNγ( 284. 06 ± 94. 31 ng / L vs 217. 47 ± 45. 76 ng / L,P < 0. 05) than the deteriorated group. The response rates of patients with acute,subacute,acute- on- chronic,and chronic liver failure were 66. 67%,85. 71%,86. 36%,and50%,respectively. Conclusion Continuous artificial liver PE therapy can effectively remove pro- inflammatory cytokines from plasma and thus improve the clinical outcomes of patients with liver failure.