Abstract Yellow/orange-emitting Ba2Mg(PO4)2: Eu2+ phosphors with uniform particle size distribution were successfully prepared by Pechini sol-gel method. The emission spectra of Ba2-xMg(PO4)2: xEu2+ phosphor displayed one broad band centered at about 560 nm which can be assigned to the 4f65d1→4f7 transitions of the Eu2+. Along with the increasing of the Eu2+ doping amount the emission peak intensity increased till the Eu2+ concentration ratio is 4 mol%. In Ba2Mg(PO4)2: Eu2+ phosphors, Eu2+ ion occupy two different lattice sites by substitution for Ba2+ ions. with the increase of the doping concentration of Eu2+ ion, the ability for Eu2+ enter into the first site of Ba2Mg(PO4)2 in the lattice is increasing.