1. A capsule endoscope, comprising: illumination means that includes a light emitting element for illuminating an object; imaging means for imaging the object; and a transparent cover having a center of curvature, said transparent cover covering the illumination means and the imaging means; wherein the imaging means includes an objective optical system and an image detecting element; an entrance pupil position of the objective optical system is arranged so that its center is located substantially at the center of curvature of the transparent cover; and the illumination means is positioned relative to the image detecting element, when viewing the capsule endoscope from the object side, so that an area that is symmetrically positioned about the optical axis of the objective optical system from a light emitting area of the illumination means overlaps an area of the image detecting element but does not overlap any area of the image detecting element that is used for picture image detection.