Although many new scintillation materials are developed, CsI: Tl is still prevailing because of its high scintillation efficiency. In this work, CsI: Tl thin films were fabricated by vacuum thermal evaporative deposition method and their morphology properties and growth orientation were observed by SEM and XRD. Photoluminescent spectra were used to measure the luminescent properties of the CsI: Tl thin film. The results show us the film formation process of CsI: Tl thin film and analyze the effect of film formation process and the deposition rate on the orientation of the CsI: Tl thin film. (C) 2017 Elsevier B.V. All rights reserved.