In this experiment, high crystallinity manganese doped and potassium doped tungsten oxide nanowires were successfully prepared by CVD method. The structure and composition of the nanowires were characterized by scanning electron microscopy (SEM) for morphology study, transmission electron microscopy (TEM) for microstructure study, energy dispersive spectroscopy (EDS) for composition study, X-ray diffraction (XRD) for crystal structure study and X-ray photoelectron spectroscopy (XPS) for chemical valence study. The resistivity of the single nanowires doped with manganese and potassium was measured to be 1.81*10^-5 Ω-m and 1.93*10^-5 Ω-m, respectively, which was much higher than that of the un-doped wires (8.27*10^-6 Ω-m), confirming the effect of increasing resistivity due to doping. Interestingly, the doping leads to the phase transition from monoclinic to metastable hexagonal tungsten oxide nanowires, the structure of which is known for its hexagonal electron channels. The introduction of impurity atoms reduced the rate of electron-hole pair recombination and the hexagonal structure provided efficient charge transfer and enhanced the catalytic efficiency of the tungsten oxide nanowires, resulting in a catalytic efficiency of 98.5% for the manganese doped tungsten oxide nanowires and 97.7% for the potassium doped tungsten oxide nanowires after four hours of degradation of methylene blue. Also, the gas sensing response for 20 ppm ethanol shows a positive dependence of doping, with the manganese doped and potassium doped responses of 14.4% and 29.7%, higher than the un-doped response at 250^oC. These properties make the doped tungsten oxide nanowires excellent candidates for photocatalytic and gas sensing applications.