A series of first- and second-generation supramolecular dendrimers (SDs) was prepared via host–guest interaction from the cyclodextrin trimer and oligoethylene glycol (OEG)-based threefold dendritic guests. These SDs are water soluble at room temperature but show characteristic thermoresponsive behavior at elevated temperatures. Their thermoresponsiveness was investigated by UV–Vis spectroscopy and dynamic light scattering measurements. Supramolecular complexation from a mixture of two dendritic guests with different hydrophilicity was performed to check the feasibility to tune the phase transition temperatures of codendrimers. Based on temperature-varied 1H NMR spectra, it was found that the SDs start to decompose when the OEG units are dehydrated.