ZnO nanowire-based ultraviolet (UV) photodetector was proposed and fabricated by depositing interdigitated Au film on vertically well aligned ZnO nanowires. It was found that the deposited Au film form good ohmic contact with the underneath ZnO nanowires. Upon UV irradiation, it was found that the detector current was increased by more than 2.5 times. It was also found that the corresponding time constant for turn-on transient was tau(on) = 3.125 ms while that for turn-off transient was tau(off) = 36.92 ms.