This book introduces the synthesis and modification of 3D hierarchical porous graphene materials and presents various applications of it. By directly constructing a 3D graphene framework with sp2 hybridization and hierarchical porosity, this book is aimed to bridge the gap between 2D ideal nanostructure and 3D practical materials by systematically studying the growth mechanism, synthetic methodology, customized application, and system promotion of 3D hierarchical porous graphene (hpG) materials. The achievements presented offer a valuable contribution to the fundamental research and the industrial development of graphene with significantly improved performance and also inspire further research into various nanomaterials beyond graphene.