An endoscope includes a distal end body provided at a distal end of an insertion part to be inserted into a body cavity, a light guide attached into the distal end body to emit light for illuminating the body cavity, a tube fitting hole provided in the distal end body such that any one of plural lens holding tubes is fitted therein, and a positioning step formed in the tube fitting hole to establish contact with any one of positioning end faces of the first lens holding tube and the second lens holding tube. The plural lens holding tubes hold respective lens units to diverge the light emitted, and have a common outer diameter and a common axial length defined as a distance between a distal end face and the positioning end face of each of the plural lens holding tubes.
