The nanocrystalline TiO 2 film electrodes were prepared by sol-gel method at different calcining temperatures, which had characteristics of different film thickness, uniform transparency, as well as high photoelectric and mechanical stability. Photoelectric measurements show that calcining temperature and film thickness could remarkably influence the photoelectric properties of the electrodes. The film calcined at 450℃ is anatase phase with high crystallinity and strong photoelectric activity, and shows the largest photocurrent. When the temperature is lower than 450℃, the film has weaker crystallinity because of a large number of defects in the film, and this is not favorable for the transport of the photogenerated carriers. And at a temperature higher than 450℃, the photocurrent of the electrode is decreased due to anatase-rutile phase transition in the film. The increase in film thickness is favorable to the enhancement of ultraviolet light (UV) absorption amount, which would improve the photoelectric activity of the film. But, excessive thickness will increase the recombination rate of the electron-hole pairs, and result in a reduction in electrode's photoelectric activity. In addition, the response sensitivity and stability of the photocurrent produced in the electrode are related to bias potential. At a potential of 0.4 V, the electrode shows a saturated photocurrent of 30.8 μA and a response time of ~1 s, suggesting that the prepared TiO 2 film electrode can be used for making UV sensors.Keywords: special function inorganic nonmetallic materials, nanocrystalline TiO 2 film, photoelectric property, UV sensor.Nanocrystalline TiO 2 is a very important inorganic semiconductor function material with a wild band gap of 3.0-3.2 eV. Owing to its characteristics of selective absorption for UV light, it has been extensively applied in photocatalysts, dye-sensitized solar cells and UV absorption coatings [1][2][3] . However, strong UV absorption of TiO 2 film, especially UV photo-to-current conversion applied to device is seldom studied. Our investigations showed that TiO 2 film can just be used for the fabrication of UV sensor because of the distinctive UV absorption characteristics and the sensor will be superior to the traditional silicon-base UV sensor. Firstly, the relatively wide band gap makes the TiO 2 film show an intensive photo-to-current response to UV light under 340 nm, but no response to visible light has ever been found [4] . This property makes the film very suitable for the UV detection against the background of infrared and/or visible light. So, the UV sensor will not only have great antijamming ability, but also a high sensitivity and resolution. Secondly, because the detector has prominent properties, such as good chemical stability, corrosion and elevated temperature resistances [5] , it can be widely applied in the special fields of ultraviolet astronomy, combustion engineering, flame detection, missile wake flame detection, etc. Furthermore, as a semiconductor device, the UV sensor based on th...