Provided are an optical information reproduction device and a method therefor with which the influence of reference light reflected from the surface of a disk can be reduced, thereby enabling data to be reproduced in a stable manner in an optical information reproduction device that uses holography. The information reproduction device, which reproduces from a recording medium information that has been recorded on the recording medium by the formation of a hologram, is equipped with: a light output unit that emits laser light; an optical system that generates reference light from the laser light emitted from the light output unit; an objective lens that reproduction signal light reproduced by the reference light with which the recording medium has been irradiated enters; a light detector that receives the reproduction signal light propagated by the objective lens; a medium-reflected light reduction unit that reduces the amount of medium-reflected light (generated when the recording medium reflects the reference light) with which the light detector is irradiated; and a control unit that controls the operation of the information reproduction device.