A vehicle interior lighting device includes a light source which is installed at an end of an instrument panel of a vehicle. Light emitted from the light source propagates from the instrument panel toward a door panel, and is projected on a surface of a door trim of the door panel. A decorative pattern element is installed on a light emitting side of the light source. As light from the light source passes through the decorative pattern element, the light can create a pattern on a surface of the door trim. Because the light source is installed on the instrument panel spaced from the door trim rather than on the door trim itself, light can be projected on a large area of the door trim. Furthermore, an impressive feature of a decorative pattern which changes in accordance with a door opening angle can be achieved.