A liquid absorbing device includes: a liquid absorber containing fibers and an anionic absorbent resin designed to absorb a liquid; a container having a feed port to which the liquid is supplied, a storage section that is connected with the feed port and that stores the liquid absorber, an inflow section configured such that part of the liquid flows into when the liquid is supplied to the storage section, and a communicating portion that connects the storage section with the inflow section; and a detection unit that is provided in the inflow section and that is configured to detect a surface of the liquid in the inflow section.