A long persistent phosphorescence S rAl 2 O 4 :Eu 2+ ,Dy 3+ phosphor powder was prepared by high temperature solid state reaction in a reducing atmosphere.XRD research o n its structure indicates that all th e synthestized aluminate is SrAl 2 O 4 crystal.The study of SrAl 2 O 4 :Eu 2+ ,Dy 3+ spetra indicates that the luminescence spectra of SrAl 2 O 4 :Eu 2+ ,Dy 3+ is the broad band spectra peaking at 520nm,and the ex-citation spectrum ranges from 300nm to 500nm.The measurement of the phosphorescence shows that the persiste nt time of the phosphores-cence lasts more than 12hours.The re sistance of SrAl_2O_4:Eu~(2+),Dy~(3+) to temperature and water was also stu died.