Objective To explore the diagnostic and prognostic value of neutrophil/lymphocyte ratio (NLR) in chronic and acute hepatic failure associated with hepatitis B. Methods 102 patients with hepatitis B in our hospital from January 2016 to December 2018 were selected, 64 patients with hepatitis B cirrhosis and 38 patients with chronic and acute hepatic failure, and 100 healthy volunteers were selected as controls, the level of NLR was compared. Results The NLR of chronic and acute liver failure group were significantly higher than that of control group, chronic hepatitis B group and hepatitis B cirrhosis group (P<0.05). The area under ROC curve of NLR in NLR diagnosis of chronic and acute liver failure was 0.865, P<0.05, and the cut-off value was 3.28, the sensitivity and specificity were 86.50% and 70.50%. The NLR of death patients with chronic and acute liver failure was significantly higher than that of survival patients (P<0.05). The area under the ROC curve of NLR for predicting death in patients with chronic and acute liver failure was 0.806 (P<0.05), and the cut-off value was 3.61, the sensitivity was 88.90% and the specificity was 60.00%. Conclusion NLR has a good application value in the diagnosis and prognosis prediction of hepatitis B-related chronic and acute liver failure, and is worthy of clinical use.