An applicable use of thermosensitive porous gel for dewatering of organic slurry was investigated. The gel was synthesized with N-isopropylacrylamide (NIPAm) as monomer and N,N'-methylenebisacrylamide (MBAA) as cross-linker. The porous gel was obtained by simple radical polymerization at higher temperature than the LCST (Lower Critical Solution Temperature) of the N-isopropylacrylamide polymer. At such a high temperature, phase separation occurs with the progress of polymerization, and a porous structure is formed. The porous gel swells and shrinks about 100 times faster than non-porous gel. The porous structure develops with an increasing concentration of the crosslinker. In this research, the plate-like porous gel with a support was prepared to improve the mechanical strength of the porous gel. A stainless steel net was used to support the porous gel. The effect of the support on the swelling properties of the gel was examined, and the dewatering of organic slurry by using such a plate-like porous gel was examined. The plate-like gel with the support swelled anisotropically. The gel with the support was strong enough to use repeatedly for dewatering the organic slurry. The water content of the slurry decreased from 91 to 60%, and the water-absorbing rate increased by increasing the concentration of cross-linker used to prepare the gel. The dewatered cake was easily removed from the plate-like gel surface. The repeated dewatering did not much influence the dewatering rate of the gel within 50 times of recycling.