Tm-doped Fiber Lasers (TDFL) have the advantages of compact structure, excellent cooling capacity, good beam quality and high non-linear effect threshold etc. Theoretically, its quantum conversion efficiency can be up to 200%. The laser generated by TDFLs at the wavelengths from 1.7 μm to 2.1 μm has wide applications in many fields. The absorption spectrum and level structure of Tm3 , the advantages and disadvantages of three different pumping methods and the research progress of high power TDFLs at home and abroad are presented in brief. Finally, the preliminary view on the future development of high power TDFLs is given.