Abstract: Optical fiber hydrogen sensors uses optical fiber as the medium of light transmission or sensing, and realizes hydrogen detection based on the physical and chemical properties of hydrogen sensitive materials. It has excellent characteristics such as intrinsic safety, strong stability, small volume light weight and good reusability, which makes it become one of the research hotspots in the field of hydrogen sensing and optical fiber sensing. The action mechanism and characteristics of typical hydrogen sensitive materials were introduced. Several typical optical fiber hydrogen sensor technologies and new progress according to the modulation mechanism of hydrogen sensitive materials were reviewed, a new optical fiber hydrogen sensor technology based on stimulated Raman gain or dispersion was introduced, and finally the problems to be solved in the practical application of optical fiber hydrogen sensor from the aspects of the key technology and environmental adaptability were analyzed, as well as the future research direction was prospected.