Photoluminescence spectra of AlxGa1-xAsySb1-y layers (x = 0.2-0.5, y = 0.02-0.03) grown by liquid-phase epitaxy on GaSb substrates were studied in a wide temperature range (14-295 K). The temperature changes of energy and intensity of the layer and substrate emission were measured. Linear part of the temperature-induced energy shift of the Al0.20Ga0.80As0.02Sb0.98 band-to-band emission exhibits a slope of -0.3 meV/K and -0.45 meV/K at temperatures 150 K and 295 K, respectively.