Temperature-responsive water absorbents, poly(sodium acrylate-co-stearyl acrylate) hydrogels, were synthesized by means of ordinary radical copolymerization of acrylic acid (AAc), stearyl acrylate (SA), and N,N-methylenebisacrylamide (MBA), and following alkali treatment. The SA hydrogels absorbed sufficient amount of water (70 ml/g resin) and exhibited thermosensitive volume-phase transition despite the presence of polyelectrolyte units such as PNaAAc. It is well known that polyelectrolytes prevent the typical thermosensitive hydrogels, poly(N-isopropylacrylamide)s (PNIPAm), from exhibiting their thermosensitive volume-phase transition. The SA hydrogels softened up and absorbed amounts of water above their phase transition temperature (T c ; about 45 o C). That is, the SA hydrogels absorbed more water at 50 o C than that at 25 o C. It is interesting that the thermosensitivity of the SA hydrogel in the water-absorption was the opposite tendency to that of the NIPAm hydrogel. Furthermore, we could regulate the water-absorption capacity of the hydrogel by controlling the incubation temperature, and could squeeze the absorbed water from the water-saturated hydrogel by cooling the incubation temperature to 25 o C from 50 o C.