Spectrophotometer

The utility model relates to the technical field of quality detection, and particularly discloses a spectrophotometer which comprises a main shell, a grating and an optical element, and the optical element comprises a photosensitive element arranged on a first photosensitive diode circuit board, a photosensitive element arranged on a second photosensitive diode circuit board and an ultraviolet light source arranged on a light source circuit board. A liquid outlet end and a liquid inlet end are arranged at the left end and the right end of the main shell respectively, a liquid inlet fixing plate and a liquid inlet part are arranged at the liquid inlet end, and the liquid inlet fixing plate, a first sealing ring, an absorption cell and a second sealing ring are sequentially arranged in the main shell from the liquid inlet end to the liquid outlet end; the liquid inlet part extends towards the interior of the main shell along the liquid inlet fixing plate to form a first embedded limiting part and an extrusion p