A review. TiO2 is n-type, wide band-gap and environmentally friendly semiconductor with good biocompatibility and stability. On the one hand, owing to the large surface area, TiO2 nanomaterials possess unique chem., phys., optical, electronic, and photocatalytic properties. On the other hand, a large amt. of the TiO2 nanostructures were prepd., characterized and available for construction of sensor due to the tremendous efforts from scientists and materials engineers. These bestow the TiO2 nanomaterials be used as an extremely versatile component to construct a wide range of sensing devices for detn. of chems. in aq. media. This work aims to review the recent applications of the TiO2 nanomaterials for fabrication of electrochem. sensors, electrochem. biosensors, photocatalytic sensors and photoelectrocatalytic sensors.