Abstract: With the rapid development of nanometer science, there will be much higher standard on nanometrology technology. So far, the uncertainty of measurement can be realized sub-nanometer and even picometer in the range of dozens of micrometers. The current main technologies used in nanometrology have been reviewed, which include the laser interferometer, beat frequency F-P interferometer, X-ray interferometer, optical and X-ray interferometer, frequency measuring system and optical frequency comb technology.