Films of Mn1−x Fe x Se (x = 0–0.45) solid solutions were flash-sputtered. We measured the transmission spectra of the films in the wavelength range 200–1000 nm at room temperature. From these spectra, we calculated the absorption coefficients and determined the fundamental absorption edge, the position of which is shifted from 2.65 eV in MnSe to 2.30 eV in solid solutions of compositions x = 0.20–0.45.