Diffuse large B-cell lymphoma is a heterogeneous group of diseases. If first diagnosed and treated regularly, nearly half of the patients can be cured, but the other half may be of the refractory relapsed type, which is divided into germinal center type GCB and non-germinal center type non-GCB according to B-cell markers. Nowadays, genetic tests may be done to classify lymphoma into more detailed categories, such as ABC and GCB, and some may have poor prognosis, but also in GCB, the prognosis is different. Therefore, the most basic tests may be required to confirm the diagnosis, and the clinical assessment of staging, i.e., the extent of lesions, may be done to distinguish between GCB and non-GCB, and further genetic sequencing may be done to further refine the classification if available. Although there are currently no corresponding drugs based on gene sequencing, it is possible that as biomedicine advances, the typing of diffuse large B may become more and more refined, and individualized treatment may be done more and more finely.