BaMgAl 1 0 O 1 7 :Eu 2 + (BAM) blue phosphor particles with improved photoluminescence (PL) intensity under vacuum ultraviolet (VUV) excitation were prepared by a spray pyrolysis process. In order to improve the PL intensity, Er 3 + and Nd 3 + ions were used as co-doping elements. The VUV characteristics of BAM:Eu 2 + ,M + (M=Er, Nd) were monitored with varying the Er 3 + and Nd 3 + content in order to find the optimal co-doping concentration when they were prepared by spray pyrolysis. It was found that doping Er 3 + or Nd 3 + enhances the PL intensity of BAM:Eu 2 + blue phosphor particles. In particular, the M 3 + doping effect on the PL intensity was pronounced when the prepared BAM:Eu 2 + ,M 3 + particles were excited by 172nm VUV. The maximum intensity was obtained when the M 3 + content was 1.0at% with respect to Ba element. The PL intensity of BAM:Eu 2 + ,M + (M=Er 3 + , Nd 3 + ) particles was also further improved by producing them in a spherical shape, which was successfully achieved by controlling the spray solution. The optimized BAM:Eu 2 + ,M + particles had about 10% higher PL intensity than that of the commercial particles, which are made by a conventional solid-state reaction.