A fluorescence observation apparatus comprising a light source having a single light-emitting portion for emitting white light and excitation light simultaneously and radiates the white light and the excitation light a light guide that guides the radiated white and excitation lights and simultaneously irradiates the white and excitation lights light onto a specimen a white-light-image acquisition unit that receives return light of the white light coming from the specimen and acquires a white-light image a fluorescence-image acquisition unit that receives fluorescence excited in the specimen by the excitation light and acquires a fluorescence image an illumination-light filter that is disposed between the light-emitting portion and a radiation exit end of the light source, and satisfies the following conditional expression, Pf(λw)
