A separating device separates liquid absorbent fibers from a material including the liquid absorbent fibers of an absorbent article and impurities. The separating device includes: a case a partition member that divides a space in the case into a first space and a second space an insertion port for inserting the material into the first space, while the material is made to ride on an airflow a rotation member housed in the first space, the rotation member agitating and opening the material and a discharge port for discharging the liquid absorbent fibers, of the material that has been opened with the rotation member, from inside the first space, while the liquid absorbent fibers are made to ride on an airflow. The partition member had a plurality of through holes that communicate with the first space and the second space. The second space includes a suction port that suctions air inside the second space, and the suction port sucks in the liquid absorbent fibers that are floating in the second space, the liquid absorbent fibers having passed through the through holes of the partition member.
