Graphene is one of the most promising materials in nanotechnology. From a theoretical point of view, it provides the ultimate two-dimensional model of a catalytic support. Its unique physical, chemical and mechanical properties are outstanding, and could allow the preparation of composite-materials with unprecedented characteristics. Even though the use of a single graphene sheet as a catalytic support has not yet been reported, some promising results have already been obtained with few-layer graphene. In this review, we will briefly discuss the most relevant synthetic routes to obtain graphene. Then, we will focus our attention on the properties and characterization techniques of graphene that are of relevance to catalysis, with emphasis on adsorption. After presenting an overview of the most common and effective preparation methods, we will discuss the catalytic application of graphene and graphene-based composites, with particular attention on energy conversion and photocatalysis.