Abstract: Tertiary lymphoid structures (TLSs), also known as tertiary lymphoid structures or ectopic lymphoid structures, are organized aggregates of immune cells that develop later in life in non-lymphoid tissues and that are structurally and functionally similar to secondary lymphoid structures. Additionally, TLSs are often associated with non-neoplastic diseases, such as autoimmune diseases and chronic inflammatory disorders. The presence of TLSs in a variety of tumors has been revealed in recent studies to be strongly associated with patient prognosis; however, its role in predicting prognosis varied in different types of tumors, which may be related to the location, maturity, and function of TLSs in tumor tissue. Currently, a comprehensive identification of the state profile of TLSs is insufficient, which limits our assessment of its potential as a prognostic marker. In this study, we comprehensively analyzed the distribution characteristics of TLSs in different tumor types and explored its role in tumor therapy, as well as the potential and value of TLS as a prognostic predictive marker.