The invention belongs to the field of luminescent materials, and discloses an electroluminescent material and a preparation method thereof. The electroluminescent material has a genera chemical formula of N1-xR2O4:xLn, zM, wherein N is one or two of Zn, Ca, Sr and Ba; R is one or two of Al and Ga; Ln is one or two of Tm<3+>, Tb<3+>, Eu<3+>, Sm<3+>, Ce<3+> and Dy<3+>; M is one or two of Ag, Au, Pt and Pd metal particles; and x is more than or equal to 0.0001 and less than or equal to 0.2, and z is more than 0 and less than or equal to 1*10<-2>. For the electroluminescent material provided by the invention, by means of introducing the metal particles and using a surface plasma resonance effect generated on metal surfaces, the luminous intensity can be increased by 60 percent; meanwhile, the preparation method is simple in operation, is easy and pollution-free, is easy to control, and facilitates industrial production.