We report the development of high-speed carbon nanotube (CNT) based infrared (IR) sensors which operate at room temperature. When a single CNT is manipulated between two different metal electrodes, a Schottky diode is formed at the CNT-metal interface, so photocurrent is generated when there is IR illumination. The devices exhibit a fast optical response time of 15 μs and the response time is limited by the readout circuit during the measurement. Beside, we proved CNTs are less temperature-dependent. Dark current of CNTs changes by a factor of 10 for 200°C drop in temperature, and photocurrent is also maintained in the same level. These values indicated nanotube can be used as an excellent IR sensing material with high-speed, stable and reliable performance under non-cryogenic cooled environment.