This paper presents a low-temperature (≃300°C) process for preparing transparent conducting anatase Nb-doped TiO2 (TNO) films on glass by sputtering. An amorphous film composed of an oxygen-rich bottom layer and oxygen-deficient top layer was deposited at room temperature. This film was then annealed in a reducing atmosphere in order to crystallize anatase. The oxygen-rich bottom layer behaved as a seed layer during crystallization of the top layer, resulting in lower crystallization temperature and significant improvement in crystallinity. The TNO polycrystalline films obtained by post-deposition annealing at 400°C exhibited resistivity of 6.4 × 10-4 Ω cm and absorption of less than 10% in the visible region. The low-temperature process developed here was applied to fabrication of TNO films on plastics and glass with low glass-transition temperature.