Thymol had been confirmed to be applied to prevent the growth of bacteria and function as an antioxidant to maintain the quality of food products. It is known that a number of components of essential oils including thymol are suitable to form inclusion complexes with β-Cyclodextrin, since they fit the hydrophobic cavity tightly. The β-cyclodextrin-thymol(β-CD-thymol) inclusion complexes were prepared by the saturated water solution method. SEM results showed that the lattice of β-CD-thymol inclusions was different from hydrogen-bond-type crystal lattice of β-CD and β-CD-water inclusions; the disappearance of high-energy water molecules in the β-CD cavity was observed from SAT data; the aromatic ring of the thymol was included in the β-CD cavity, according to the FTIR data. Besides, according to the calculation of chemical structure, molecular size of thymol was estimated. These results supported a successful formation of the inclusion and the preliminary structure of host-guest inclusions was constructed, indicating the -CH3 is close to the β-CD narrower rim, while the -CH2 and OH group is close to the wide one.