A room temperature oxygen sensor based on TiO 2 /graphene device was developed with an enhanced sensing performance by UV light. A logarithmic relationship between the sensing response and O 2 concentration (from 134 ppm to 100%) was obtained. The sensor also shows an improved response and recovery with the durations of 193 s and 135 s at RT and atmosphere pressure, respectively. Herein, UV light was employed to excite electron–hole pairs in the TiO 2 film and the photogenerated electrons were scavenged by graphene and percolated to the collecting electrode, while the holes recombined with the electrons within TiO 2 film. This process will deplete the electron further thereby changing the conductivity of the device rapidly resulting in a much better sensing signal.