An insertion unit 2 of an endoscope 1 includes a distal section 8, a bending section 9 that can bend freely, and a soft section 10 having flexibility in that order from the distal end thereof. The soft section 10 has as the distal part thereof a small-diameter portion 10a, a large-diameter portion 10b, and a tapered portion 10c linking the small-diameter portion 10a and large-diameter portion 10b. At least part of the tapered portion 10c is located ahead of a point that is 70 cm away from the distal endoscope end. When the insertion unit 2 is inserted into the large intestine, if the distal section 8 is moved the shortest distance to the cecum, the distance from the anus to the distal section 8 is known to generally range from approximately 60 cm to approximately 70 cm. Therefore, at least part of the tapered portion 10c is located ahead of the point that is 70 cm away from the distal endoscope end, whereby excellent insertion efficiency is ensured. <；IMAGE>；
