An endoscope system with a hollow cylinder and bellows moving mechanism is provided. The system includes a cylinder having a head unit mounted by a camera devices, a front fixing unit connected to the head unit which is installed to an outer circumference of the cylinder and fixed to an inner wall of an organ, a rear fixing unit slidably installed at the outer circumference of the cylinder and fixed to the inner wall of the organ, and a moving unit between the front fixing unit and the rear fixing unit for moving the head unit in the organ by an extension and contraction when the front fixing unit or the rear fixing unit fixes the head unit to the inner wall of the organ. The moving unit includes a double bellows and forms a hermetic space with the outer circumference surface of the cylinder.