A medical apparatus of the present invention has a light source section capable of irradiating an object with an excitation light and a reference light alternately, an image pickup section that picks up images of fluorescence that is emanated when a fluorescent substance existing in the object is excited, and reflected light that is the reference light reflected in the object respectively, a pixel addition processing section that pixel addition processing of making signals corresponding to a plurality of pixels in a fluorescence image obtained by picking up of an image of the fluorescence be a signal corresponding to one pixel, a brightness adjusting section that makes adjustment so that a brightness ratio of the fluorescence image to which the pixel addition processing is applied and a reference light image obtained by picking up of the image of the reflected light has a constant value, and an image processing section that applies pixel interpolation processing to the fluorescence image to which the adjustment of brightness is applied and performs image synthesis so that the fluorescence image to which the pixel interpolation processing is applied and the reference light image to which the adjustment of brightness is applied are included in a same observed image.
