A front end of an endoscope includes both a lens and an image sensor. There is provided a guide wire hole. The endoscope is easily inserted along a guide wire while a diameter is reduced in the front end in an insertion direction. The endoscope includes a lens which is disposed in the front end in the insertion direction, and receives incident imaging light, an image sensor disposed in a rear portion of the lens, and on which an image of the imaging light is formed, a holder which covers the lens and the image sensor, and having the guide wire hole through which the guide wire penetrates, and a flexible tubular sheath connected to a rear end portion of the holder, and into which a cable conductively connected to the image sensor is inserted.
