A novel phosphor, Sr2LaNbO6:Mn4+, is synthesized by conventional solid-state reaction. The phosphor can be excited at 300-500 nm and emit a deep-red light. An emission band peak of 694 nm is observed from the spin-forbidden transition E-2 -> (4)A(2) of Mn4+ ions. Energy transfer between the Mn4+-Mn4+ pairs decreases fluorescence decay time from 0.815 ms to 0.512 ms. The resistance of luminescence against thermal impact is also investigated by emission spectroscopy at heating temperatures from 300 K to 500K. The calculated activation energy Delta E (similar to 0.345 eV) demonstrate good thermal stability of the phosphors. All these results indicate that the phosphor can be applied in white-light-emitting diodes. (C) 2017 Elsevier Ltd. All rights reserved.