An optical fiber vibration sensor includes a polarization-diversity loop based interference unit having a polarization-maintaining fiber configured to generate an interference spectrum, a polarizing beam splitter connected to the polarization-maintaining fiber and configured to split light incident from a narrowband light source into two polarized beams, and a polarization controller connected to the polarization-maintaining fiber or the polarizing beam splitter and configured to control the two polarized beams split through the polarizing beam splitter, and an optical fiber vibration test unit combined to the polarization-maintaining fiber so as to apply an external vibration to the polarization-maintaining fiber, wherein light output intensity of the polarization-diversity loop based interference unit is converted to an electrical signal by a light detector, and the vibration applied to the polarization-maintaining fiber may be measured through the optical fiber vibration test unit.