By selecting some glass compositions the transparent glass-ceramics containing mullite crystal phase are obtained. The luminescent behaviors of these glasses and glass-ceramics were investigated according to the absorption spectrum and fluorescence spectrum. The results indicate that the emission intensity of glass-ceramic will enhance when the crystallization temperature was increased in a limited range, as a result the effective luminescent efficiency of Cr 3+ ion will increase. The increase of Cr 3+ ion concentration will cause the increase of emission intensity of glass-ceramics, but it will cause concentration quenching and decrease the effective luminescent efficiency of Cr 3+ ion. The origin of 688 nm emission shoulder in the glass-ceramic fluorescence spectrum is discussed, and it is suggested that the 700 nm and 688 nm emission should be attributed to the split of 2E energy level.