A wireless endoscope system includes: a data storage unit that stores imaging data as storage data at a time at which a still image display signal is switched from a first state indicating an execution of a moving image display to a second state indicating an execution of a still image display; an image quality control unit that controls image quality of a plurality of pieces of still image data such that an image quality of a piece of still image data generated later a becomes higher; a data-selecting unit that selects the moving image data or the plurality of pieces of still image data on the basis of the still image display signal; and a transmission unit that transmits the moving image data or the plurality of pieces of still image data selected by the data-selecting unit in a wireless manner.