Abstract: The distributions and expression of the T helper 17 (Th17) cells and interleukin 17 (IL-17) are found in a verity of tumor tissues. However, their functions in tumorigenesis, which play anti-tumor or promote tumor roles, have not yet a final conclusion. Therefore, it is ecessary to go further study of their functions in tumor microenvirnment. It is wished that in the process of cancer treatment, people would hasten benefit avoids kill and improve the therapeutic effect.