Nanostructures have unique characteristics, such as large specific surface areas, that provide a wide range of engineering applications, such as electronics, optics, biotics, and thermal and fluid dynamics. They can be used to downsize many engineering products; therefore, new nanofabrication techniques are strongly needed to meet this demand. A simple fabrication process with high throughput is necessary for low-cost nanostructures. In recent years, three-dimensional (3D) nanostructures have attracted much attention because they dramatically opened up new fields for applications. However, conventional techniques for fabricating 3D nanostructures contain many complex processes, such as multiple patterning lithography, metal deposition, lift-off, etching, and chemical-mechanical polishing. This paper focuses on controlled-acceleration-voltage electron beam lithography (CAV-EBL), which can fabricate 3D nanostructures in one shot. The applications of 3D nanostructures are introduced, and the conventional 3D patterning technique is compared with CAV-EBL and various 3D patterning techniques using CAV-EBL with nanoimprinting technology. Finally, the outlook for next-generation devices that can be fabricated by CAV-EBL is presented.