A comprehensive study of UV-irradiation of Er-activated solid luminophores on f-f-luminescence of Er³⁺ions in metal oxide (ZrO₂, La₂O₃) and fluoride (LaF₃, YF₃) matrices has been carried out. Both increasing (LaF₃, YF₃), and decreasing (ZrO₂, La₂O₃) of luminescent emission intensity under monochromatic excitation at 377 nm caused by UV irradiation of dispersed samples have been observed. A possible mechanism of the established effect is briefly discussed