An interference measuring device comprises: a light source; a beam splitter that causes the light to diverge into a reference optical path and a measurement optical path and that outputs a combined wave in which reflection light passed the reference optical path and reflection light passed the measurement optical path are combined; a reference light diverging part that causes the light diverged into the reference optical path, to further diverge into a plurality of optical paths and that causes reflection light beams respectively passed the optical paths to be input into the beam splitter; and a plurality of reference mirrors that are respectively arranged in the optical paths such that optical path lengths of the optical paths are different from each other, and that reflect reference light. An interference image is imaged by varying the optical path length of either the reference optical path or the measurement optical path.