An endoscope includes an imaging unit configured to image a subject and output image data, a moving-image generation unit configured to generate moving-image data from the image data output from the imaging unit, a still-image generation unit configured to generate still-image data from the image data output from the imaging unit, a release instruction unit configured to receive an image-recording instruction from a user, a first wireless communication unit configured to sequentially change a wireless channel to transmit test data and transmit the still-image data to the reception device when the release instruction unit receives the image-recording instruction, a second wireless communication unit configured to transmit the moving-image data to the reception device using a wireless channel different from the wireless channel currently used by the first wireless communication unit, and a first setting unit configured to set a wireless channel determined from communication quality information.