Pt wires were fabricated by using electron-beam (EB) and Ga focused-ion-beam (FIB) irradiation while providing C5H5Pt(CH3)3 gas through a nozzle. Electron transport properties of the wires were investigated. The resistance of the EB-deposited wires was quite high as deposited but was reduced by 3-4 orders of magnitude after 400-500°C annealing. The electron transport of the as-deposited EB-deposited wire was dominated by the variable range hopping and the Coulomb blockade simultaneously, and showed the antilocalization effect after 400°C annealing. The electron phase-breaking length in the EB-deposited wire with 400°C annealing, which was derived from a theoretical fitting, is ≈10 nm at ≈4 K and increases with decreasing temperature. This means that 10-nm fabrication technology and improvement of coherence length are required for coherent vacuum nanoelectronics.