Hepatitis B virus（HBV）infection poses a significant global health burden，with chronic infection driving progression to cirrhosis，hepatic failure，and hepatocellular carcinoma（HCC）. Mounting evidence implicates immune dysfunction and microbiota dysbiosis as core drivers of disease progression across all HBV infection stages. Gut and tissue-specific microbiota alterations disrupt innate/adaptive immunity，fueling inflammation，immunosuppression，and tumor immune evasion in chronic and end-stage disease. This review synthesizes mechanisms of immune-microbiota interplay in HBV pathogenesis and explores their translational potential for diagnostics and targeted interventions，including microbiota modulation and microbial biomarker applications.

Hepatitis B virus（HBV）infection poses a significant global health burden，with chronic infection driving progression to cirrhosis，hepatic failure，and hepatocellular carcinoma（HCC）. Mounting evidence implicates immune dysfunction and microbiota dysbiosis as core drivers of disease progression across all HBV infection stages. Gut and tissue-specific microbiota alterations disrupt innate/adaptive immunity，fueling inflammation，immunosuppression，and tumor immune evasion in chronic and end-stage disease. This review synthesizes mechanisms of immune-microbiota interplay in HBV pathogenesis and explores their translational potential for diagnostics and targeted interventions，including microbiota modulation and microbial biomarker applications.

It has been discovered that intestinal fungi play important roles in microecological systems of human body, which affect the human health by influencing gut microbiota directly or indirectly. This article reviews the research progress about the fungi-bacteria interaction, and effects of intestinal fungi and their products on host’s health. The article also discusses the correlation of intestinal fungi with inflammatory bowel disease, colorectal cancer, HBV-related liver diseases, metabolism-associated fatty liver disease and alcoholic liver disease, indicating that intestinal fungi are widely involved in the development of human diseases.