the invention discloses a rare earth organic red luminous material and preparing method of 390-420 nm luminous semiconductor chip in the luminous material domain of semiconductor diode, which displays Eubeta3Lx, wherein the Eu is rare earth iron Eu3+; beta is first organic ligand beta-diketone; L is second organic ligand with 2 nitrogen atoms or one oxygen atom as ligand atom; the molar rate of subscript 3 and x in the corresponding composition is x=1 or x=2. The preparing method comprises two steps: first, synthesizing Eubeta3 .2H2O complex; second, synthesizing Eubeta3Lx complex. |