A portable lighting device includes: a coherent light source; a shaping optical system that shapes coherent light emitted from the coherent light source; and a diffractive optical element that diffracts the coherent light shaped by the shaping optical system to a surface to be irradiated (IP). The diffractive optical element is rotatably supported. The surface to be irradiated is lighted in a pattern depending on a diffraction pattern of the diffractive optical element.