Observational studies, especially cohort studies, are important tools for understanding disease progression, treatment, and prognosis in the real world. Observational cohort studies which involve over 500 patients are currently launched by South Korea and the United States. China, which has more patients, doesn't have a cohort of patients with lymphoma. So the primary objective of this study was to establish an observational cohort of patients with lymphoma in China and follow up the patients for a long period of time to provide basic support for clinical research and drug development, and continuously improve patient outcomes and quality of life. The secondary objective is to collect information about diagnosis, treatment, follow-up and prognosis of lymphoma.