This paper presents the design, batch-fabrication and testing of a piezoresistive cantilever beam microaccelerometer for automobile airbag applications. Silicon proof-mass has been bonded symmetrically for self-diagnostic capability and zero transverse sensitivity of the microaccelerometer. Microfabrication process, including a simple silicon etch-stop method for beam thickness control, has been developed for mass production lines. Fabricated devices show a resonant frequency of 2.15kHz and a sensitivity of 34μV/g/V with a nonlinearity of 2% at 100Hz. The present fabrication processes provide simple, practical and effective means for the reproducibility and mass production of the accelerometers.