Mo-doped ZnO (MZO) films with different Mo concentration (0～1 at%) were prepared on Al2 O3 (0001) substrates by sol-gel spin coating route. It was found that the MZO films with ZnO hexagonal wurtzite structure were highly c-axis orientation. The electrical properties of MZO films can be significantly improved by the heat-treatment in vacuum. The resistivity of the films initially decreases with the increase of Mo content and then gradually increases with a further increase of Mo content. The lowest resistivity of 0.13 Ωcm was obtained at a Mo content of 0.4 at%. The carrier concentration and Hall mobility were measured and discussed to understand the electrical transport characteristics. The high average transmittance (>85%) in near-infrared region (800～2000 nm) indicates the possible use of MZO films in photoelectric device can widen absorption spectrum range.