Abstract: In an analysis device that irradiates light from three or more light sources onto a cell, embodiments proposed herein prevent a reduction in the intensity of light from each light source, and are provided with at least a first light source, a second light source, and a third light source, and an optical system that guides light from the respective light sources onto a cell. The optical system is provided with a second light source optical element that reflects the light from the first light source and transmits the light from the second light source, and a third light source optical element that reflects the light from the first light source that has been reflected by the second light source optical element and the light from the second light source that has been transmitted through the second light source optical element, and transmits the light from the third light source.