Nitride semiconductor laser element and illumination light source module

A nitride semiconductor laser element, comprising:

• a stacked structure including a plurality of semiconductor layers including a light emitting layer, the stacked structure including a pair of resonator end faces located on opposite ends;
• and
• a protective film including a dielectric body and disposed on at least one of the pair of resonator end faces, wherein:
• the protective film includes a first protective film, a second protective film, a third protective film disposed in stated order above the stacked structure, a reflectance adjusting layer disposed above the third protective film and including at least one dielectric film, and a fourth protective film disposed between the third protective film and the reflectance adjusting layer,
• the first protective film is amorphous,
• the second protective film is crystalline,
• the third protective film is amorphous,
• the fourth protective film contains nitride or oxynitride, and
• the at least one dielectric film included in the reflectance adjusting layer includes a dielectric film that is in contact with the fourth protective film, and is an amorphous oxide film having a noble gas atom concentration less than 2 atomic percent.