To obtian a real fluorescent spectrum while keeping high sensitivity, in a spectrofluorophotometer achieving an increase in the intensity of exciting light allowed to irradiate a sample using a reflecting mirror and the enhancement of the collection efficiency of fluorescence.

Shading shutters 21 and 22 are respectively provided so as to be inserted in and pulled out of the gaps between a sample cell 3, a concave mirror 4 and a plane mirror 5, and the fluorescent spectrum Fclose of a standard sample wyile being shaded by the insertion of the shutters 21 and 22 and the fluorescent spectrum Fopen of the standard sample while being not shaded by removing the shutters 21 and 22 are respectively otained. The ratio Fopen/Fclose of both spectra is calculated in a correction factor operating part 91 and standardized to calculate a correction factor Q to store the same in a correction factor memory part 92. A fluorescent spectrum Funk of high sensitivity is obtained without using the shutters 21 and 22 at the time of measurement of a target sample and divided by the correction factor Q to calculate the real fluorescent spectrum from which the effect of the reflecting wavelength characteristics of the concave mirror 4 and the plane mirror 5 is removed.