Copolymers of 6-O-vinyladipoyl-D-glucose (VAG) and N-isopropyl acrylamide (NIPAm) were synthesized by radical polymerization. The number-average molecular weights of the copolymers were 3 X 10(4) approximate to 6 x 10(4). The observed segment composition of copolymers at the feed molar ratio (VAG 25/NIPAm 75) was VAG 10/NIPAm 90. The polymerization rate of the VAG monomer was slower than that of the NIPAm monomer. The lower critical-solution temperature of copolymers measured with a light-scattering photometer and a differential scanning calorimeter increased with increasing VAG segment composition. The increase in transition temperature was accompanied by a decrease in transition heat.