We report metrology methods to characterize nanowires. In this work, representative devices and test structures, including nanoelectromechanical switches, non-volatile nanowire memory devices with SONOS structure, and both transfer-length-method and Kelvin test structures, have been developed to investigate the electrical and mechanical properties of the silicon nanowires. These methods and test structures can be readily applied to other (non-Si) semiconductor nanowires/nanotubes.