The lymphatic system is ubiquitous throughout the body, and problems with the lymphatic system often manifest themselves first in a particular lymph node, so it is important to beware of swollen lymph nodes in one place without any reason. Of course, this is the lymphoma within the lymph node system, but there are also lymphatic vessels accompanying the lymph node system, such as the stomach and intestines, and if malignant changes occur in this area, it is the malignant lymphoma of the organ, which is different from the lymphoma of the lymphatic system. Malignant lymphoma mostly occurs in the lymph nodes and can be multiple or solitary, and it can start in any place other than the lymph nodes. Since lymphomas are tumorigenic proliferations, their malignancy and course can be very different depending on histological features, but their clinical manifestations are all similar. Since lymphatic tissue has human immune function, malignant lymphoma is also a malignant actual tumor of the immune system. The lymphatic system is the body’s defense system, which mainly plays a role in surveillance as well as resistance to foreign infections. The lymphatic system has two parts, one is the lymphatic organs and the other is the lymphatic vessels. The lymphatic organs mainly include lymph nodes, spleen, thymus and tonsils, etc. Normally, lymph nodes are very small, within 0.5 cm, and when they encounter bacterial or viral invasion, the lymph nodes near the inflammation are easily enlarged, usually 1 cm, and the lymph nodes swell when the inflammation comes and subside when the inflammation disappears. There is no reason for the swelling of lymph nodes, and in the case of primary lymphoma, they are usually persistently enlarged and painful. The incidence of malignant lymphoma is higher in Europe, North America, Saudi Arabia and certain African countries than in most Asian and African countries. The disease has a low incidence and mortality rate in China; however, because of our large population base, the actual total number of cases is estimated to be around 15,000 per year. And it often occurs in young adults. The rate of increase of lymphoma patients is very fast in these years, and some data in Shanghai show that the rate of increase of lymphoma incidence is about 4% per year. According to domestic and international statistics, lymphoma is the ninth most common malignant tumor among men and the tenth most common among women. The relationship with gender factor is that there are slightly more men than women. Malignant lymphomas are divided into two categories: Hodgkin’s disease (HD) and non-Hodgkin’s lymphoma. Each category can also be divided into multiple subtypes based on histopathological features. The incidence ratio of Hodgkin’s disease and malignant lymphoma differs significantly. The statistical analysis of 4023 cases of malignant lymphoma conducted by the editorial board of our tumor control research showed that Hodgkin’s disease accounted for 29.1% and non-Hodgkin’s lymphoma accounted for 70.9%. Which groups of people are more likely to develop lymphoma? Basically, the main research results in the last five and ten years have led to a better understanding of the development of lymphoma. Although it is not yet clear, we now know that viruses, such as EBV and the familiar HTLV virus, are associated with the development of lymphoma. In addition, immune dysfunction is also closely related to the incidence of lymphoma, and the incidence of lymphoma is significantly higher in patients with immune disorders. In addition, bacteria such as Helicobacter pylori, gastric ulcer and chronic gastritis are also associated with the development of lymphoma. There are also genetic, physical, and chemical factors, and physical factors are probably more important, such as radiation. Since the 1930s, the effectiveness of treatment of the disease has gradually improved. In recent years, the use of rational and planned comprehensive treatment, the efficacy of further improvement. Hodgkin’s disease can be cured in 60% to 80% and non-Hodgkin’s lymphoma can be in long-term remission in more than 50%, which has become an encouraging area of oncology research.