PROBLEM TO BE SOLVED: To provide an endoscope light source device having an improved optical coupling efficiency to the endoscope under a high degree of design freedom.SOLUTION: An endoscope light source device 100 comprises: a laser light source unit 110 that emits a laser beam； an LED light source unit 130 that emits an LED beam； and an optical path merging member 160 that merges the optical path of the laser beam and the optical path of the LED beam. The etendue of the laser light source unit 110 is smaller than the etendue of the LED light source unit 130. The optical path merging member 160 has a reflection surface 162 that reflects the LED beam, and has, in a region of the reflection surface 162, an opening 164 that lets the laser beam pass through. The optical path merging member 160 reflects the LED beam such that the central axis of the optical path of the LED beam reflected by the reflection surface 162 matches the central axis of the optical path of the laser beam that has passed through the opening 164.【課題】高い設計自由度の元に、内視鏡スコープへの光結合効率が向上された内視鏡光源装置を提供する。【解決手段】内視鏡光源装置１００は、レーザ光を出射するレーザ光源部１１０と、ＬＥＤ光を出射するＬＥＤ光源部１３０と、レーザ光の光路とＬＥＤ光の光路を合流させる光路合流部材１６０を有している。レーザ光源部１１０のエタンデュは、ＬＥＤ光源部１３０のエタンデュよりも小さい。光路合流部材１６０は、ＬＥＤ光を反射する反射面１６２を有し、反射面１６２の領域内にレーザ光を通過させる開口１６４を有している。光路合流部材１６０は、反射面１６２によって反射されたＬＥＤ光の光路の中心軸が開口１６４を通過したレーザ光の光路の中心軸に一致するように、ＬＥＤ光を反射する。【選択図】図１
