It is known that motion of free particles in curved space-times is deeply connecting with symmetry of space-times. In particular, it has been revealed that besides isometry “hidden symmetry” is important in black hole space-times since it was discovered first in Kerr space-time. Therefore it is interesting question to study how hidden symmetry works in higher-dimensional black hole space-times. In this talk, we will study hidden symmetry of five-dimensional black ring space-times together with a “Geomtrization” method. According to Maupertuis’ principle, Hamiltonian dynamics result in geodesic problems on the corresponding manifolds, which is called “Geometrization.” In the first half of this talk, beginning with a review of hidden symmetry, we will introduce the geometrization carefully. After that, hidden symmetry of five-dimensional black ring space-times will be discussed.