The structures of Au particles on CeO2 surfaces were observed by an analytical transmission electron microscopy (TEM) equipped with annular dark field scanning transmission electron microscopy (HAADF-STEM) systems. The Au/CeO2 model catalysts were prepared by using the poly-crystalline CeO2 substrates. The Au particles of 2-5 nm in diameter were deposited on the substrates. The preferential orientation relationship of (111)[1-10]Au//(111)[1-10]CeO2 was frequently observed in profile-view HRTEM images on CeO2 (111) surface. High resolution HAADF-STEM images were also obtained for Au-CeO2 interfaces. The position of atomic columns of Au and Ce at Au-CeO2 interface is directly investigated from HAADF-STEM images. The structure of the interfaces between Au particles and CeO2 (111), (100), (110) surfaces were discussed.