Thulium (Tm) doped Ga2O3 films were deposited on sapphire substrates by pulsed laser deposition (PLD) with changing Tm compositions in the targets. Energy dispersive spectroscopy results reveal that films with different Tm compositions can be tailored by changing the Tm composition in the targets. X-ray diffraction and Raman spectra analysis indicate that all films have the monoclinic structure. Photoluminescence measurements demonstrate that the emission peaks at 460, 650 and 800 nm are observed from the Tm3+ 4f intrashell transitions from (1)G(4) excited states to the H-3(6), F-3(4), and H-3(5) states, respectively. The results suggest that PLD is a promising method for obtaining high quality Tm doped Ga203 films, which paves the way for the fabrication of optoelectronic devices based on Ga2O3 films. (C) 2017 Elsevier B.V. All rights reserved.