In recent years, hepatitis B virus (HBV) infection patients with diffuse large B cell lymphoma (DLBCL) have shown an upward trend, and its etiology is complex and treatment is difficult, so it has received extensive attention from scholars at home and abroad. Based on the review and analysis of the research of domestic and foreign scholars, this paper further discusses the mechanism of the occurrence and development of DLBCL caused by HBV infection and the clinical prognosis of related patients, and finally finds that at the genomic and transcriptome levels, HBV may mainly induce the changes of BCL6, FOXO1, ZFP36L1 and other genes, and activate various regulatory genes through HBV's X protein, thereby inducing clonal proliferation of lymphocytes and eventually forming lymphoma. For the clinical prognosis assessment, the clinical prognosis assessment mainly analyzes and compares the patient's age of onset, sex, organ involvement, international prognostic index (IPI), lactate dehydrogenase (LDH) level, proliferation index (Ki-67), bcl-2, bcl-6, inflammatory index and other factors, aiming to put forward a theoretical basis for the clinical diagnosis and treatment of DLBCL and basic research.