The f→f transition emission of Eu^2^+ in LiAl5O3 and α-Al2O3 is found for the first time, disappearing of the f→f transition emission of Eu^2^+ and there existing a new band emission in mixture phases of α-Al2O3 and γ-Al2O3. The experimental results are discussed in detail by crystal structure data of hosts and theory of crystal field and covalence. Partial charge of Eu^2^+ and ionic percentage of Eu-O(F) and M-O(F) in hosts are calculated by Sanderson's theory, a content explanation of the experimental phenomena being obtained.

Key words: ALUMINIUM OXIDE, EUROPIUM, CRYSTAL FIELD THEORY, FLUORESCENCE CHARACTERISTIC, COVALENT CRYSTALS