To solve the problems of low basic repetition rate and wide output pulse width of high repetition frequency femtosecond fiber laser, the main development direction and bottleneck of high repetition frequency fiber ultra-short pulse laser were studied. The mode-locking technologies of high repetition frequency femtosecond fiber lasers were described in detail, such as SESAM mode-locking, NPR mode-locking and NALM mode-locking. The difficulties and technical problems in the field of high repetition frequency femtosecond fiber lasers were discussed. Based on this, the latest research progress in the following fields was summarized, including the exploration of new high repetition frequency mode-locking technology, the expansion of high repetition frequency fiber femtosecond laser in the output wavelength and the research of ultra-stable high repetition frequency fiber optical comb. Finally, the typical applications of GHz femtosecond light source in the fields of optical fiber lidar, optical frequency comb and biological detection were briefly described, and their prospects were prospected.