The features of ocean wave and the importance of its energy harvesting are intro duced. Afterwards, several typical ocean wave energy harvesters (OWEHs) are pres ented, including their structures, characteristics, and applications, in which a snake-like ocean wave energy harvester proposed by the authors is emphasized. By the example of the harvester, the difficulties and the key technologies of OW EHs are presented in terms of wave modeling, structural parameter selection and optimization as well as wave adaptive tuning scheme. Finally, the develop trend of OWEH is prospected according to the current problem in their research and ap plication.