In order to enhance security of a parked vehicle, an image transmitting device to be mounted on a vehicle includes: a checking unit that checks, at a parking place of the vehicle, communicability with an external device outside of the vehicle, that is, whether an image can be transmitted from the parking place to the external device; a providing unit that provides notification information based on a result of the checking by the checking unit; a capturing unit that captures an image while the vehicle is parked; and a transmitting unit that transmits the image captured by the capturing unit to the external device.