Diatoms are three-dimensional (3D) natural biomaterials produced by unicellular algae with unique nano- and micro-morphologies, with numerous excellent structures. Diatom nanotechnology is a new research field emerging in recent years. It has been studied and applied in many fields such as biology, sensor, adsorption, nano-transport and new energy. Due to its special porous three-dimensional structure, high specific surface area and the ability of other conductors or semiconductor materials to combine and transform, it has been widely used in energy storage and low cost natural electrode materials. According to the research status of this material both at home and abroad in recent years, the application of diatom-based composites to energy applications in other energy equipment such as supercapacitors, batteries and solar cells is demonstrated.