Rare-earth-doped strontium titanate ceramics yielding the formula Re0.02Sr0.97TiO3 (Re-ST, Re=La, Sm,Gd,Er) were prepared by solid-state reaction route. All Re-ST ceramics had single cubic perovskite structure similar to pure SrTiO3 (ST). The grain size of Re-ST ceramics dramatically decreased to 1-10m, depending on different rare-earth elements, as compared to similar to 30m of pure ST. The relative dielectric constant of Re-ST ceramics (epsilon(r)=2750-4530 at 1kHz) showed about 10-15 times higher than that of pure ST (epsilon(r)=300 at 1kHz), whereas the dielectric loss of Re-ST ceramics still remained lower than 0.03 (at 1kHz) at room temperature. Under 0-1.63x10(6)V/m bias electric field testing conditions, the epsilon(r) of Re-ST ceramics at room temperature changed within 14%. The P-E results indicated that the Re-ST ceramics were linear dielectrics. Together with their relatively high breakdown strength (E-b>1.4x10(7)V/m), the Re-ST ceramics could be very promising for high-voltage capacitor applications. Meanwhile, the temperature stability of the epsilon(r) of Re-ST ceramics was evaluated in a temperature range of -60 degrees C-200 degrees C.