The biodegradable cholesteryl-(epsilon-caprolactone)170 (Chol-(CL)10) functionalized polymer was synthesized and then investigated for inclusion complexation with ot-cyclodextrin (alpha-Cl)). The supramolecular inclusion complexes (ICs) were in detail characterized by fourier transform infrared (FTIR), H-1-nuclear magnetic resonance, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide angle X-ray diffraction (WAND), and C-13-NMR, respectively. All analyses indicated that oligo(E-caprolactone)10 chains of the Chol-(CL)10 were included into the hydrophobic of alpha-CD cavities and their original crystalline properties were completely suppressed. Moreover, the ICs of biodegradable Chol-(CL)10-functionalized polymer with alpha-CD had a channel-type crystalline structure similar to that formed between the poly(s-caprolactone) and alpha-CD. Further more, The TGA analysis revealed that the ICs had better thermal stability than their free components due to the inclusion complexation, suggesting that the complexation stabilized the polymer included in the CD channels. (c) 2007 Wiley Periodicals, Inc.