Abstract: The correct N staging of non-small cell lung cancer(NSCLC) is very important for the option of treatment. ¹⁸F-FDG PET/CT as a new imaging method which combines the advantages of functional and anatomic images has become more and more accurate in the N staging of NSCLC. Numerous researches have proved some risk factors that influenced the mediastinal lymph node metastasis. This review focus on the new parameters and new technologies which improve the accuracy of the N staging of NSCLC recently.