This paper presents the temperature characteristics of a silicon nanowire transistor and its use as a temperature sensor. The OMEN nanowire simulation tool was used to investigate the temperature characteristics of the transistor. Current–voltage characteristics with different values of temperature for three orientations were simulated. The metal–oxide–semiconductor (MOS) diode connection suggests the use of the silicon nanowire transistor as a temperature nanosensor. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.