A frictional electric generator, a device including the frictional electric generator, and a method for manufacturing the frictional electric generator are provided. The frictional electric generator includes a first frictional unit and a second frictional unit arranged opposite to each other. The first frictional unit includes a first output electrode, and the second frictional unit includes a second output electrode. A composite layer is arranged in at least one of the first frictional unit or the second frictional unit, and is provided with a surface having concave-convex nanostructures as a frictional surface. The first output electrode and the second output electrode are configured to form a capacitor.