Endoscope and linear heat sink

The present invention is an endoscope, comprising a tube part (20), a heat emitter (40) within the tube part (20), and a heat conductor (43) made of graphite which is connected to the heat emitter (40). The heat conductor (43) is a graphite sheet or a stack thereof. The graphite sheet has an area of 4 mm 2 or more, and heat conductivity of 1950 W/m∙K or more in the a-b plane direction at 25°C. The present invention is also a linear heat sink which is wound in a helical shape such that a portion of the graphite sheet or the stack thereof is mutually overlapping. The thickness of the graphite sheet ranges from greater than 50 nm to not more than 9.6 μm.