Abstract: Objective　To investigate the risk factors affecting the prognosis of hepatitis B virus associated chronic acute liver failure (ACHBLF) and to establish a prognostic model. Methods　A total of 277 ACHBLF patients were included in this study. The general clinical characteristics, liver function, coagulation function, routine blood test and the survival of the patients were collected. In the training cohort, univariate and multivariate Cox regression analysis was performed to evaluate the independent factors, and a new prognosis model was established. The prognostic prediction ability of the new model was evaluated in training cohort and validation cohort. Area under the receiver operating characteristic (ROC) curve was used to evaluate the predictive value of the models. Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model. Kaplan-Meier survival curve was used to predict the prognosis of patients. Results　The total bilirubin (TBIL), direct bilirubin and alkaline phosphatase were lower in the validation group than those in the model group. Data of age, proportion of male, fibrinogen, lymphocytes (LYMPH), monocytes and white blood cells (WBC) were higher in the validation group than those in the model group (P＜0.05). The increased TBIL and WBC and the decreased LYMPH and prothrombin activity (PTA) were independent risk factors for ACHBLF death in the model group. The new model TPWL=1.059×TBIL-1.272×PTA+1.090×WBC -0.602×LYMPH and the optimal critical value of TPWL model was -17.52 according to the ROC curve of the model group. The coincidence rates of the model in the modeling group and the validation group were 91.75% and 81.93%, respectively. The areas under the ROC curve were 0.961 and 0.914, respectively. The Hosmer-Lemeshow test results showed that P values were 0.210 and 0.062, respectively. Kaplan-Meier survival curve analysis showed that the survival rate of patients with TPWL score ≥ -17.52 was significantly lower than that of patients with TPWL score＜-17.52. Conclusion　The predictive model established in this study has a high value in evaluating the prognosis of ACHBLF patients.