We report optical, electrical and magnetotransport properties of oxygen deficient SrTiO3 (SrTiO3-x) thin films fabricated by pulsed laser deposition technique. The oxygen vacancies (Ovac) in the thin film are expected to be uniform. By comparing its electrical properties to those of bulk SrTiO3-x, it was found that Ovac in bulk SrTiO3-x is far from uniform over the whole material. The metal-insulator transition (MIT) observed in the SrTiO3-x film was found to be induced by the carrier freeze-out effect. The low temperature frozen state can be reexcited by Joule heating, electric and intriguingly magnetic field. © 2011 American Physical Society.