Semiconductor laser element, semiconductor laser device, method for manufacturing semiconductor laser device, and gas analyzer

The invention provides a semiconductor laser element, a semiconductor laser device, a method for manufacturing the same, and a gas analyzer. A distributed feedback type semiconductor laser element (3) has a diffraction grating (3M) formed on a waveguide (3L), stably outputs single-mode light, and increases the intensity of the light. The waveguide (3L) is provided with: a diffraction grating section (301) in which a diffraction grating (3M) is formed; and a flat section (302) having a region in which the diffraction grating (301) is not formed and which is wider than the diffraction grating section (301). The flat portion (302) has a connection portion (303), the connection portion (303) has a region in which the width continuously changes as the connection portion (303) faces a connection site with the diffraction grating portion (301), a high reflective film (HR) is provided on an end surface of the flat portion (302) on the opposite side to the connection portion (303), and a low reflective film (AR) is pr