In this study, Eu 3+ -doped LiMgBO 3 phosphor was successfully synthesized by a solid-state reaction. Techniques such as X-ray power diffraction, scanning electron microscopy, and photoluminescence spectra (PL) were used to characterize the phosphors. Upon excitation by near ultraviolet (395nm) and blue (466nm) light, the LiMgBO 3 :Eu 3+ phosphor exhibits intense red emission at 615nm, corresponding to the forced electric dipole 5 D 0 → 7 F 2 transition of the Eu 3+ ions. Furthermore, co-doping the LiMgBO 3 :Eu 3+ phosphor with the sensitizer Bi 3+ effectively extends the absorption strength of 7 F 0 → 5 L 6 and 7 F 0 → 5 D 2 transitions, caused by the wide absorption band of Bi 3+ . The enhancement in the luminescence intensity of LiMg 0.75−y BO 3 :Eu 3+ 0.25 ,Bi 3+ y phosphor due to the addition of Bi 3+ ions indicates energy transfer from Bi 3+ to Eu 3+ . Results suggest that the quadrupole–quadrupole interaction is the major energy transfer mechanism in LiMg 0.75−y BO 3 :Eu 3+ 0.25 , Bi 3+ y phosphors.