The present invention concerns a method and a device for measuring polarization dispersion of an optical fiber which is particularly useful in telecommunications, and which has a finer resolution of this measurement in comparison to methods and devices known in the art. The device consists of an interferometer (51), a low coherent light source (16), a detector (25) for generating an interferogram, and a module (52) connected in series with the optical fiber to be measured (20), this module comprising a high dispersion birefringent fiber (53) of stable, known polarization, two pairs of fiber bundles (55, 56) for adjusting the polarization controller (54) and for aligning the principal polarization modes of the optical fiber to be measured and the birefringent fiber, and an electronic processor (21) for measuring the separation of the lateral peaks on the interferogram resulting as a function of predetermined adjustments to the polarization controller. The polarization dispersion of the fiber to be measured is deduced by measuring the different separation values.