Apparent molar heat capacities of the hydroxypropyl-alpha-eyelodextrin, hydroxypropyl-beta-cyclodextrin, and hydroxypropyl-gamma-eyelodextrin in aqueous solution have been determined at 298.15 K allowing the evaluation of their heat capacities at infinite dilution in water. The calorimetric data do not indicate evidence of aggregation of the hydroxypropyleyclodextrins. The differences in behavior of these modified cyclodextrins compared to linear oligosaccharides, and native cyclodextrins are analyzed.