An endoscope comprising: an operation portion including an inner space; an optical image conducting member configured to conduct an imaged optical image and including a coupling end portion arranged in the inner space of the operation portion; a display portion coupled to the operation portion configured to be rotated about a central axis as a rotational axis of an elongated insertion portion of the endoscope relative to the operation portion, including an inner space and configured to display the imaged optical image conducted by the optical image conducting member; and an electrical cable configured to transmit an electric signal, extending between the inner space of the operation portion and the inner space of the display portion, including a connecting end portion connected to the display portion and including a winding portion formed by additional length so as not to prevent movement of the display portion relative to the operation portion, characterized by a wound portion provided in the inner space of the operation portion or the inner space of the display portion, and including a diameter increasing portion configured to increase from a proximal end side to a distal end side along the rotational axis, wherein the winding portion is configured to be wound around the wound portion and the diameter increasing portion is configured to support the winding portion such that movement of the winding portion toward the operation portion beyond the diameter increasing portion is restricted, and the winding portion is configured such that when the display portion is rotated in a first direction relative to the operation portion, a proximal end portion of the winding portion is pulled in the rotational direction, and the winding portion is acted so as to be wound around the wound portion, and when the display portion is rotated in a second direction relative to the operation portion, which is opposite to the first direction, the proximal end portion of the winding portion is pushed forward in the rotational direction, and the winding portion is acted so as to be released from the wound portion. an operation portion including an inner space; an optical image conducting member configured to conduct an imaged optical image and including a coupling end portion arranged in the inner space of the operation portion; a display portion coupled to the operation portion configured to be rotated about a central axis as a rotational axis of an elongated insertion portion of the endoscope relative to the operation portion, including an inner space and configured to display the imaged optical image conducted by the optical image conducting member; and an electrical cable configured to transmit an electric signal, extending between the inner space of the operation portion and the inner space of the display portion, including a connecting end portion connected to the display portion and including a winding portion formed by additional length so as not to prevent movement of the display portion relative to the operation portion, characterized by a wound portion provided in the inner space of the operation portion or the inner space of the display portion, and including a diameter increasing portion configured to increase from a proximal end side to a distal end side along the rotational axis, wherein the winding portion is configured to be wound around the wound portion and the diameter increasing portion is configured to support the winding portion such that movement of the winding portion toward the operation portion beyond the diameter increasing portion is restricted, and the winding portion is configured such that when the display portion is rotated in a first direction relative to the operation portion, a proximal end portion of the winding portion is pulled in the rotational direction, and the winding portion is acted so as to be wound around the wound portion, and when the display portion is rotated in a second direction relative to the operation portion, which is opposite to the first direction, the proximal end portion of the winding portion is pushed forward in the rotational direction, and the winding portion is acted so as to be released from the wound portion.