An all fiberoptic accelerometer, based on Michelson interferometry, has been developed theoretically and experimentally. It makes use of an oscillating mass suspended by a transduction fiber in a mass support. The interferometric configuration is formed by a 3 dB single-mode fiberoptic beam splitter, on two distal endfaces of which high-reflectance aluminum films were directly coated and served as reflecting mirrors. An ac phase tracking modulation–demodulation scheme has been employed to process the signal. The performance of a prototype of the accelerometer has been investigated, and the results indicated that the measured frequency spectrum is qualitatively consistent with the theoretical prediction, and the detected output wave forms are also in good agreement with that of the applied simulation signals. In addition, the constraint on the lateral movement of the acceleration-sensitive mass with two specific diaphragms has been experimentally verified, nevertheless, it needs to be optimized further. © 1998 American Institute of Physics.