Since the International Union Against Cancer (UICC) first promulgated the TNM staging in 1968, the TNM staging of lung cancer has been revised six times in more than 30 years, and the current staging used worldwide was promulgated in 2002, which continues to follow the staging criteria of the 5th edition in 1997 and has been widely used in clinical diagnosis and treatment of lung cancer. However, there are still more opinions and disagreements in the industry about the current staging. The current staging does not fully reflect the essential biological behavior of lung cancer. Birth of new staging: The International Association for the Study of Lung Cancer (IASLC) proposed to revise the staging of lung cancer in 1998. After more than 10 years of efforts, the new staging collected clinical data of 67,725 lung cancer patients from 46 research centers in 19 countries between 1990 and 2000, and the number of clinical cases enrolled far exceeded the total number of cases in the previous 6 editions, and was not only limited to Europe and the United States. The general structure of the 7th edition is still similar to the 5th and 6th editions, but some changes have been made to the details, which are more scientific and convincing than the previous editions. Changes of the new staging: The main changes of the new TNM staging of lung cancer include: T1 is divided into T1a (≤2cm) and T1b (>2cm and ≤3cm); T2 is divided into T2a (>3cm and ≤5cm, or combined with other factors and ≤5cm) and T2b (>5cm and ≤7cm); the original T2 tumor with maximum diameter >7cm is classified as T3; the original T4 primary tumor Those with metastatic nodules in the lung lobe where the original T4 primary tumor was located were classified as T3; those with metastatic nodules in the ipsilateral lung lobe other than the lobe where the original M1 primary tumor was located were classified as T4; those with malignant pleural effusion, malignant pericardial effusion, and metastatic nodules in the pleura were classified as M1; M staging was divided into M1a and M1b, i.e., those with malignant pleural effusion, malignant pericardial effusion, metastatic nodules in the pleura, and metastatic nodules in the contralateral lung were classified as M1a, and those with metastases outside the chest cavity were classified as M1b. distant metastases were M1b; T2bN0M0 was changed from stage IB to stage IIA; T2aN1M0 was changed from stage IIB to stage IIA; and T4N0-1M0 was changed from stage IIIB to stage IIIA. The new staging still has limitations: The study data are from a wide range of sources, with no data yet from Africa, South America, and the Indian subcontinent. Some countries with large populations (e.g., China, Russia, Indonesia) provided too small a proportion of the overall data. Treatment patterns vary widely among study sites, leading to differences in outcomes and having some impact on the final statistical survival rates. This study was primarily retrospective, and the inevitable bias in data presentation by individual study centers affected the randomization and objectivity of the statistical results. In addition, the investigators believe that more data are needed to verify the reliability of the revisions.