The output of pendulous accelerometer based on silicon-glass bonding is sensitive to the stress in the torsion beam. During the micromachining process, the large thermal stress can be generated due to the thermal expansion coefficient mismatch between the Si layer and glass substrate, which results in thermal drift of the accelerometer. Therefore, an accelerometer with stress isolation buffering structure is proposed in this paper. The buffering structure consists of folded-beam and inner suspension frame, which can limit the thermal stress in the torsion beam and reduce the thermal drift of the accelerometer effectively. The ANSYS software is adopted to analyze the natural frequencies and thermal stress distribution of the sensor. The result show that the natural frequency of the first mode is 1 352 Hz, which is much smaller than that of other disturbance modes. The sensitivity of the accelerometer is 0.386 pF/g(g=9.8 m/s2). The thermal stress of the accelerometer without stress isolation structure is about 100 MPa and mainly concentrates at the end of torsion beam. While the stress of the accelerometer with stress isolation structure mainly concentrates at the folded-beam, and the stress in torsion beam is about 1.7 MPa, which amounts to only 1.7% of the former. This accelerometer is fabricated by silicon-glass bonding and ICP etch processes.