In this paper, the barium titanate nanowires (BTO NWs) were prepared by two-step hydrothermal method, then compounding with the polyvinylidene fluoride (PVDF) by spin coating method to prepare the BTO NWs/PVDF composite films. The effects of different NaOH concentrations, different reaction times and different BTO NWs doping amounts on the piezoelectric output performance of BTO NWs/PVDF composite films in the hydrothermal reactions were systematically studied, and its piezoelectric properties were compared with those of BTO NPs/PVDF composite films prepared by the commercial barium titanate nanospheres (BTO NPs). The results show that when the NaOH concentration is 10 mol/L and the reaction time is 10 h, the open-circuit voltage and short-circuit current of BTO NWs/PVDF composite film can reach 5.42 V and 1.81 μA, respectively. When the doping amount of BTO NWs is 20wt%, the open-circuit voltage and short-circuit current of the composite piezoelectric film can reach 9.34 V and the short-circuit current can reach 2.15 μA, which is 1.92 and 1.49 times that of the BTO NPs/PVDF composite film, respectively. At a load resistance value of 5 MΩ, the output power of the BTO NWs/PVDF composite film can reach 1.44 μW. After 4 000 cycles of percussion test, the BTO NWs/PVDF piezoelectric composite film shows good mechanical stability. The prepared BTO NWs/PVDF piezoelectric composite film is expected to be widely used in self-powered devices and flexible wearable electronic devices.