A series of materials such as Eu2+: CaAl2O4:, (Eu2+ ,Nd3+ ): CaAl2O4 were developed by using high temperature solid state reaction. The excitation, photoluminescence and afterglow spectra as well as the curve of afterglow decay were investigated. The role of doped rear earth ions and the long afterglow mechanism of this kind of phosphor are discussed.