A series of Ca4.99(PO4)3F:1%Eu3+, 1%X (X = Li+, Au3+, and Bi3+) nanoparticles are prepared using hydro-thermal method, with an average size of 33–62 nm. We study the improved photoluminescence properties of Ca4.99(PO4)3F:1%Eu3+ by co-doping with Li+,