A detailed investigation on photoluminescence properties and energy transfer (ET) dynamics of Ce³⁺, Pr³⁺-doped BaY₂Si₃O₁₀ is provided along with the potential X-ray excited luminescence application. The luminescence properties of Pr³⁺ are studied in VUV-UV-vis spectral range at low temperature, and the spectral profiles of Pr^{3+ 3}P₀ and ¹D₂ emission lines are determined using time-resolved emission spectra. Upon 230 nm excitation, the electron population from Pr³⁺ 4f5d state to its 4f² excited state is discussed in detail. As Pr³⁺ concentration rises, Pr^{3+ 3}P₀ and ¹D₂ luminescence possess different concentration-related properties. The incorporation of Ce³⁺ in the codoped sample produces the strong Ce³⁺ luminescence under 230 nm excitation, which is the combined result of Pr³⁺ 4f5d → Ce³⁺ 5d ET and Ce³⁺ intrinsic excitation. On the other hand, the increasingly strong ET of Ce³⁺ 5d → Pr³⁺ 4f² results in the decrease of Ce³⁺ emission intensity and the gradual deviation of Ce³⁺ luminescence decay from the single exponential in the system. By employing the Inokuti-Hirayama model, the dipole-dipole interaction is confirmed as the predominant multipolar effect in controlling this ET process, and the value of C_DA is determined to be 9.97 × 10^-47 m⁶·s^-1. Finally, the relatively low scintillation light yield of Ce³⁺-doped BaY₂Si₃O₁₀ material impedes its application potential in the scintillator field, and the cosubstitution of Pr³⁺ results in the observable decline of scintillation performance.