Due to its high specific surface area, good chemical stability and outstanding electrical properties, graphene, a class of two-dimensional allotrope of carbon-based materials, is one of ideal candidates for next generation energy conversion and storage devices. In this review, we will present an overview on electrochemical characteristics of graphene by summarizing the recent research trend on graphene for energy conversion and storage applications, such as fuel cells and supercapacitors, along with some discussions on future research directions. Display omitted ► Graphene has a high specific surface area, good chemical stability and outstanding electrical properties. ► Graphene is one of ideal candidates for next generation energy conversion and storage devices. ► This review is an overview on electrochemical characteristics of graphene. ► Particularly, graphene for fuel cells and ultracapacitor applications.