An endoscope includes: an insertion portion a first distal end face that can receive light from an observed body an opening that opens near the first distal end face a treatment instrument insertion channel communicating with the opening and inserted into the insertion portion a first detection fiber that transmits light received by the first distal end face a second distal end face that can receive the light from the observed body and that is different from the first distal end face a second detection fiber that can be inserted into a conduit and that transmits the light received by the second distal end face and a merging portion where the light transmitted by the first detection fiber and the light guided by the second detection fiber merge.
