A process for preparing an electroluminescent film which comprises causing a substrate held at a high temperature to simultaneous contact two kinds of vapors of (a) Group II element and a Group VI element or a compound thereof, capable of forming a Group II-VI compound semiconductor, and (b) a halide of an element capable of acting as luminescent centers in the Group II-VI compound semiconductor, in the presence of flowing hydrogen or an inert gas, whereby a thin electroluminescent film comprising the Group II-VI compound semiconductor and containing the element forming the luminescent centers is formed on the surface of the substrate.