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Polycrystalline Sr5LnTi3Ta7O30 (Ln=La, Nd, Sm and Y) ceramics were prepared as single-phase materials through conventional solid-state ceramics method. The structure was characterized by X-ray diffraction method and scanning electron microscopy (SEM). The dielectric properties were measured from room temperature to 400 ℃. All compounds are paraelectric phases adopting the filled tetragonal tungsten bronze (TB) structure at room temperature. At 1 MHz their dielectric constant (e) varied from 109 to 139,dielectric loss changed from 0.003 3 to 0.005 8, and the temperature coefficients of the dielectric constant (τε)moved from -710 to -880×10-6 ℃-1.