The crystallinity and luminescent property were studied on evaporated CaS:Eu thin films. The orientation of the film strongly depends on substrate temperature. Distinct orientation was not observed in films deposited below 600 °C. Above 600 °C, the films tend to have a (111) orientation. The red emitting electroluminescent device with CaS:Eu active layer prepared at 680 °C which is strongly oriented to the [111] direction shows the brightness of 180 cd/m2under 1 kHz alternate excitation.