An all-dielectric metamaterial with a simple structure and can excite toroidal dipole resonance, and that exhibits a high quality factor (Q) and high sensitivity (FOM) value is proposed. Based on the current density and electric field distribution of toroidal dipole resonance, the intrinsic physical mechanism that the metamaterial can excite the toroidal dipole is analyzed. Numerical simulation shows that the Q and FOM values of the all-dielectric metamaterial can reach more than 14000 and approximately 672.7 nm/RIU, respectively. Based on the harmonic oscillator coupling model and the electric field distribution at the resonant wavelength, the influence mechanism of spacing between the rings and thickness of the detector on the Q value and the resonant wavelength is also analyzed. This study can provide a theoretical basis for the design and preparation of high-quality toroidal dipole resonance metamaterial sensors for use in biological and chemical detection.