The phenomenon of sensitized luminescence in the Ce3+:Eu3+:Cr3+:Sm3+:YAG layer grown by LPE is reported. With higher concentration of Ce 3+ ion doped into the layer, there are new lines observed in the blue and green band of the emission spectra of this layer. The analysis of those emission lines show that they can be assigned to the radiative transition from the 5D i(i=1,2,3) higher excited levels of Eu 3+ ion directly to the ground state levels 7F j(j=0,1,2,3) because of the sensitization and energy transfer from Ce3+ ion to Eu3+ ion in YAG lattice. And this Ce3+ :Eu3+:Cr3+:Sm3+:YAG epitaxially grown layer also turns out to be a new single crystal phosphor for white emission.