Highly responsive, flexible aluminum nitride single nanowire ultraviolet photodetector (AlNNW-UVPD) is reported for the first time with the highest responsivity of 1197.5  mA  /  W along with an excellent external quantum efficiency of 584% under 254-nm UV light exposure at 30 V bias. A flexible nanoscale photodetector on a very small scale was fabricated through a scalable and highly cost-efficient hot-contact method. With this method, we were able to achieve arrays of very small size devices with gold microelectrodes of size 110  μm  ×  110  μm and narrow gaps of 4  μm between the electrodes capable of operating at 0 V (self-powered) and 30 V. Our UV sensor displayed the highest detectivity of 2.32  ×  10¹²  cm  .  Hz^1/2  .  W^−  1 as a flexible AlN single nanowire device under 30 V bias. Moreover, the device demonstrated a very good wavelength selectivity and a very fast response speed along with very high durability against bending testing. In short, highly responsive, flexible, very small, cost-effective, and durable AlNNW-UVPD can provide opportunities for multifunctional, portable, sensitive, wearable, and smart sensors in optoelectronics and flexible electronics.