Wave energy has been one of the key directions in the research of marine energy development and utilization, due to its rich resources, green, clean, renewable and other characteristics,. There have been a number of wave energy devices which were commercialized. In contrast with tidal current energy technologies, the development of the wave energy field has slowed down over the past few years. The confidence of investors have been reduced by technological drawbacks of wave energy . At the end of 2016, the situation of the wave energy development field has improved significantly.. At present, there are 21 commercialized pre projects or pre commercialization projects running in the world and several array projects have been moving forward; current installations have a power rating of 1MW. In this paper, firstly, a comprehensive survey of the current situation of wave energy technology in global has been given; Secondly, sorting of wave energy devices and comparing the advantages and disadvantages of various types of devices have been combed and the technical difficulties and challenges have been analysed. Finaly, combined with the characteristics of wave energy resources distribution of China, the future development trend of wave energy devices and the direction suggestions for wave energy development work have been given.