A Michelson interference type fiber accelerometer comprises a cylinder body, an upper limit pin, a first collimator, an optical coupler, a lower limit pin, a mass block, a second collimator, and an annular magnet; the accelerometer also comprises an optical isolator, a laser light source, a photoelectric detector and a phase demodulation circuit; the mass block is designed as a part of a Michelson interferormeter free space optical path, and is suspended by using a static magnetic repulsion magnetic flux effect, thus converting external acceleration changes into minimal displacement of the mass block; the differential fiber Michelson interferormeter can detect the phase changes caused by the mass block displacements, thus real time demodulating the sensor acceleration changes; the accelerometer uses the magnetic suspension mode to avoid the machinery damping influences, and imports a bireflection Faraday optical rotation structure to eliminate the subordinate fading influences; the Michelson interference type fiber accelerometer is high in sensitivity, good in stability, small in size, simple in making, and has good application prospects.