This paper describes the experimental results of an all polarization-maintaining (PM) fiber Michelson interferometer system. In expriment, we used a Panda PM fiber, PM polarizors fabricated through lapping and polishing (extinction ratio 3 dB, loss<0. 5 dB) , and a tapered fusion PM coupler (extinction ratio 20-25 dB, loss<1 dB). The operating point is maintained through the use of a piezoelectric phase modulator. The phase detection sensitivity has been found to be better than 10-3rad over a certain frequency range.