Photoluminescence (PL) and thermally stimulated luminescence (TSL) of CdS1-xSex nanocrystals embedded in borosilicate glass are studied. The dependence of the spectral positions of the near-edge and surface-mediated PL bands on the nanocrystal composition and size is discussed. A different temperature behaviour for the higher-energy TSL band (maximum at 360-380 K, dependent of the nanocrystal size and composition) and the lower-energy peak (broad maximum in the range 350-450 K) is discussed.