PROBLEM TO BE SOLVED: To surely remove dirt by making fluid flow to the surface of an illumination window together with an observation window.SOLUTION: At a distal end part 16a connected to an insertion part distal end of an endoscope, an air/water supply nozzle 22, an observation window 28 and first and second illumination windows 29 and 30 are provided. The first and second illumination windows 29 and 30 are disposed at positions holding the observation window 28 therebetween. At the distal end part 16a, a guide recess 35 having a level difference on a proximal end side is formed with respect to a flat surface 27c on the distal end side. The guide recess 35 is arranged at a position surrounding the observation window 28 and the first and second illumination windows 29 and 30. A bottom surface 35a of the guide recess 35 is inclined from the distal end side to the proximal end side along a guide direction of passing through the first illumination window 29, the observation window 28, and the second illumination window 30 in order from a jetting port 40 of the air/water supply nozzle 22.
