Abstract (Gd1−xEux)(BO2)3 (0≤x≤1) phosphors are synthesized by traditional high temperature solid state reaction. The photoluminescence (PL) properties of Gd(BO2)3 and Gd(BO2)3 activated with Eu3+ are investigated. The PL spectra exhibit the typical characteristic emission and excitation of Gd3+ and Eu3+ ions, and support the energy transfer taking place from Gd3+ to Eu3+ ions. The relationship between Eu3+ doping concentration and emission intensity is also studied. Even if all of the Gd3+ ions are substituted by Eu3+ ions, the concentration quenching between Eu3+ happens. However, the quenching is not complete. The luminescence decay curves are measured, and the lifetimes become short with the Eu3+ content increasing. The decreasing Gd3+ lifetimes also indicates that there exists efficient energy transfer between Gd3+ and Eu3+ ions.