Sn1-xFeXO2 (x = 0, 0.05) thin films were prepared on glass substrate using the flash evaporation technique. The samples were annealed at 773 K for 2 hrs in air atmosphere. A systematic study was carried out on the structural and optical properties of the as deposited and annealed thin films. From the X-ray diffraction analysis it was found that the Sn1-xFeXO2 films deposited at 623 K were amorphous in nature and the Sn1-xFeXO2 films annealed at 773 K exhibited the tetragonal structure of the SnO2. The optical band gap of the SnO2 thin films was found to be as 3.17 eV whereas the optical band gap of the Sn1-xFeXO2 films was found to be as 3.01 eV after air annealing. © 2014 AIP Publishing LLC.