This study focused on assessing the solubility and structural characteristics of two types of coenzyme Q 10 (CoQ 10 ) complexes: the CoQ 10 -starch and the CoQ 10 -cyclodextrin complexes. The solubility of CoQ 10 -starch complex increased significantly as the temperature was increased. However, the solubility of CoQ 10 -cyclodextrin complex reached a peak at 37 o C, and strong aggregation occurred at 50 o C. When the temperature was raised to 80 o C, the CoQ 10 -cyclodextrin complex dissociated owing to the weakening of bonds, resulting in CoQ 10 emerging at the surface of water. Therefore, CoQ 10 -cyclodextrin complexes have lower solubility, due to their reduced heat-stability, than do the CoQ 10 -starch complexes. Structural differences between the two CoQ 10 complexes were confirmed by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffractometer (XRD), and differential scanning calorimeter (DSC). The CoQ 10 -cyclodextrin complex included an isoprenoid chain of CoQ 10 , while the CoQ 10 -starch complex included both the benzoquinone ring and the isoprenoid chain of CoQ 10 . These results suggest that CoQ 10 -starch complexes possess higher heat-stability and solubility than do the CoQ 10 -cyclodextrin complexes.