Axial symmetric curved shell resonators are among the most-widely used resonators because of their high symmetry, robustness, and reliability. However, the fabrication of this kind of resonator is based on newly developed three-dimensional (3D) microelectromechanical system technologies, making it difficult to fabricate. Polysilicon shell resonator is suitable for batch fabrication owing to its compatibility with the materials and fabrication technologies used in the IC industry, which is of high value and should be studied thoroughly. A 3D polysilicon shell resonator with high symmetry was produced using silicon cave as its mold, and the fabrication process was designed and tested experimentally. The cave was formed by isotropic etching of silicon, using a mixture of HF/HNO3/CH3CHOOH with bulk ratio 15∶10∶75 as the etchant. The temperature of the etchant was controlled using a water bath to ensure that the speed of the etching does not change abruptly. The level of the wafer was maintained by a clamp with which the wafers position could be adjusted freely. The abovementioned measures ensured that the silicon caves had good properties, especially the symmetry and roughness. Then, 3D polysilicon shells with diameters ranging from 0.8 to 1.3 mm were fabricated, with the smallest roundness less than 0.4%. The roughness of the shell was less than 1 nm. The resonant properties of the fabricated shells were investigated using noncontact characterization methods facilitated by a laser Doppler vibrometer. A mechanical quality (Q) of 14 365 at 28 kHz was obtained in vacuum with a pressure of 0.2 Pa. By adjusting the bias voltage and actuated voltage, the mode-matching situation was achieved, and the relative frequency mismatch between the two degenerate four-node wineglass modes was reduced to zero.