Abstract: Single-crystalline silicon materials have laid the foundation of modern semiconductor industry. Single-crystalline silicon nanomembrane has different mechanical, optical and electrical properties from bulk silicon due to their nano-sized thickness. The most significant characteristics are high mechanical flexibility and transferability. Biocompatibility and compatibility with CMOS technology make it widely used in the field of flexible electronics. This paper reviews the properties of single-crystalline silicon nanomembrane, the fabrication techniques of flexible devices and the research progress in various fields as flexible functional devices. The development of flexible functional devices based on single-crystalline silicon nanomembrane in the future is discussed.